According to Au7o's analysis of 4,765+ owner reports, the 1999-2026 GMC Sierra 1500 has 35 documented known issues, with 15 rated critical. The most serious are AFM/DFM Lifter Collapse and Failure ($4,000-$8,000 repair), 8-Speed/10-Speed Transmission Torque Converter Shudder ($150-$4,500 repair), Electronic Brake Control Module Failure ($150-$1,500 repair), Transfer Case Unintended Shift to Neutral ($0-$0 repair), NHTSA Recall 19V645000: Declining Vacuum Pump Output Reduces Power Brake Assist, Missing Transfer Case Component Can Lock the Front or Rear Wheels Without Warning (Recall 26V289000 — Do Not Drive) ($0-$0 repair), MultiPro Tailgate Drops Open By Itself While Driving — Water Intrusion at the Handle-Cavity Release Switch ($250-$950 repair), 10L80/10L90 10-Speed Valve Body Failure — Loss of Reverse, Limp Mode, and Year-Long Parts Backorder ($900-$6,500 repair). at .
SERVICE BRAKES, HYDRAULIC:BRAKE FLUID LOW WARNING: LAMP
General Motors, LLC (GM) is recalling certain 2023 Chevrolet Silverado 1500, GMC Sierra 1500, 2023-2024 Chevrolet Tahoe, Suburban, GMC Yukon, Yukon XL, Cadillac Escalade, and Escalade ESV vehicles. The electronic brake control module software may fail to display a warning light when a loss of brake fluid occurs. As such, these vehicles fail to comply with the requirements of Federal Vehicle Safety Standard number 135, "Light Vehicle Brake Systems."
Campaign #24V67400012/09/2024
EXTERIOR LIGHTING:LIGHTING CONTROL MODULE:SOFTWARE
General Motors, LLC (GM) is recalling certain 2020-2023 Cadillac CT4 and CT5; 2021-2023 Buick Envision; and 2022-2023 Cadillac Escalade and Escalade ESV, Chevrolet Silverado 1500, Suburban, Tahoe, GMC Sierra 1500, Yukon, and Yukon XL vehicles. The daytime running lights (DRLs) may not deactivate when the headlights are on. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, "Lamps, Reflective Devices, and Associated Equipment."
Campaign #22V90300008/12/2022
ENGINE AND ENGINE COOLING:ENGINE:HARD PARTS INTERNAL/MECHANICAL
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What are the most common GMC Sierra 1500 problems?
According to Au7o's analysis of 4,765+ owner reports, the 1999-2026 GMC Sierra 1500 has 35 documented issues. The most frequently reported are: AFM/DFM Lifter Collapse and Failure, 8-Speed/10-Speed Transmission Torque Converter Shudder, Electronic Brake Control Module Failure. Of these, 15 are rated critical and should be addressed promptly.
Is the GMC Sierra 1500 reliable?
The 1999-2026 GMC Sierra 1500 has 35 known issues documented across 4,765+ owner reports. 15 issues are rated critical: AFM/DFM Lifter Collapse and Failure and 8-Speed/10-Speed Transmission Torque Converter Shudder and Electronic Brake Control Module Failure and Transfer Case Unintended Shift to Neutral and NHTSA Recall 19V645000: Declining Vacuum Pump Output Reduces Power Brake Assist and Missing Transfer Case Component Can Lock the Front or Rear Wheels Without Warning (Recall 26V289000 — Do Not Drive) and MultiPro Tailgate Drops Open By Itself While Driving — Water Intrusion at the Handle-Cavity Release Switch and 10L80/10L90 10-Speed Valve Body Failure — Loss of Reverse, Limp Mode, and Year-Long Parts Backorder and Rear-View Camera Unusable at Night — Reverse Lamps Do Not Illuminate the Camera's Field of View and 6.2L L87 V8 Connecting Rod and Crankshaft Failure — Sudden Loss of Propulsion (Recall 25V274000) and P0016 — Crank/Cam Correlation Fault from Stretched Timing Chain on 5.3L AFM V8 and P0700 — Transmission Fault Flag from Failing 6L80/6L90 Internal TEHCM and 4L60-E / 4L65-E Sun Shell Failure Causing Loss of Reverse and 2nd/4th Gear and Fuel Pump Module Failure Causing No-Start or Stalling and Rusting Brake Lines Leading to Fluid Loss and Sudden Brake Failure. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common GMC Sierra 1500 problems?
Repair costs for known GMC Sierra 1500 issues range from $0 to $15,000, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, AFM/DFM Lifter Collapse and Failure, typically costs $4,000-$8,000 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What year GMC Sierra 1500 is the most reliable?
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.
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When Issues Typically Appear
Upper Dash Pad Cracking and Interior Panel Failure in Sun-Exposed GMT800/GMT900 Trucks
40K-150K
AFM/DFM Lifter Collapse and Failure
50K-100K
Blend Door / HVAC Actuator Failure Causing Clicking Behind Dash and Incorrect Air Temperature or Mode
50K-180K
Fuel Level Sensor Failure Causing Erratic or Inoperative Gas Gauge
50K-140K
Stepper Motor Instrument Cluster Failure Causing Inaccurate Gauges
50K-150K
Direct Injection Carbon Buildup on Intake Valves
60K-100K
Front Hub Bearing Assembly Failure Causing ABS Activation, Noise, and Wheel Play
60K-150K
Knock Sensor Water Intrusion Under Intake Causing Check Engine Light and Reduced Performance
60K-150K
Rusting Brake Lines Leading to Fluid Loss and Sudden Brake Failure
70K-200K
Power Door Lock Actuator Failure Causing Intermittent or Inoperative Locking
70K-160K
Fuel Pump Module Failure Causing No-Start or Stalling
80K-180K
4L60-E / 4L65-E Sun Shell Failure Causing Loss of Reverse and 2nd/4th Gear
90K-180K
050K100K150K200K mi
Community reported
890 owners
The 8L90 8-speed and 10L80/10L90 10-speed automatic transmissions experience shuddering during light throttle acceleration, particularly at highway speeds between 35-60 mph. The issue is caused by the torque converter lock-up clutch slipping and chattering. Harsh shifts between gears, especially 1st to 2nd and 2nd to 1st, are also commonly reported.
Vibration or shudder during light acceleration at 35-60 mph
Harsh or jerky shifts between gears
Transmission slipping sensation
Shudder when torque converter locks up
Intermittent transmission hesitation
How to Fix
Transmission fluid flush with updated Mobil 1 Synthetic LV ATF HP fluid (GM part number 19417577). Torque converter replacement. Transmission control module software update. Complete transmission replacement in severe cases.
High Confidence890 owner reportsLast reported by owners Feb 2024Reviewed Feb 2026
Community reported
234 owners
An electrical signal short in the transfer case can cause it to shift to neutral without driver input while driving. This results in sudden loss of power to the wheels creating a serious safety hazard, particularly at highway speeds or when towing.
High Confidence234 owner reportsLast reported by owners Feb 2024Reviewed Feb 2026
2024-2025 Sierra 1500 trucks with the 10-speed automatic (5.3L L84, 6.2L L87 and 3.0L Duramax LZ0) are failing at very low mileage with a stuck valve-body solenoid. Symptoms: a 'Service Transmission' or 'Service Transmission — Unable to Shift Soon' message, sudden hard/slamming shifts, slipping, complete loss of reverse (owners have had to push the truck out of parking spaces), and default limp operation limited to fifth gear and reverse. Several complaints report the failure occurring under 7,000 miles. NHTSA reports cite DTC P2818 (pressure control solenoid) and P0747/P0700. The situation is compounded by a national valve-body backorder — owners document 50-plus days and in some cases over a year waiting for the part, with GM sometimes authorizing a full transmission replacement instead. Complaint ODI numbers include 11756150, 11754176, 11748050, 11744152, 11739083, 11727368, 11721983, 11694617, 11684139, 11680422, 11680435, 11654431, 11644523, 11634982 (2024) and 11711937 (2025).
GM issued TSB #25-NA-255 (Sept 22, 2025) directing technicians to REPAIR rather than replace the valve body on 2021-2024 Silverado/Sierra 1500 and full-size SUVs with the 10L80/10L90 when P0747 is set. The repair installs a new steel Feed Limit Low Valve, a higher-tension Feed Limit Valve Spring, and a new valve body spacer plate with gasket; it requires at least 7,000 miles on the vehicle and must not be used if there is significant clutch debris in the pan. No solenoid characterization programming is needed afterward. Ask the dealer specifically for the 25-NA-255 repair kit rather than accepting a backordered complete valve body. Repairs are covered under the 5yr/60k powertrain warranty for these model years. If clutch material is present, a transmission replacement is the correct call.
P0700 itself is only a flag: the Transmission Control Module has stored one or more transmission faults and is requesting the MIL. On Sierra 1500s with the 6L80 (and 6L90 on heavier variants) 6-speed automatic, the notable design issue is that the TCM is integrated into the valve body as a TEHCM (transmission electro-hydraulic control module), bolted inside the pan and sitting in 180-250°F fluid. Repeated heat cycling degrades the module and its integrated pressure switches and solenoids. When the TEHCM or a shift/pressure-control solenoid begins to fail, it sets specific sub-codes (e.g., P2534, P0742, P0761) plus the umbrella P0700, and the truck can exhibit harsh or missed shifts, slipping, or limp mode. Critically, on the 6L80/6L90 the solenoids are over-molded into the non-serviceable TEHCM and generally can't be replaced individually.
P0700 alone is not actionable — pull the transmission-specific sub-codes with a capable scanner to find the real fault. Check fluid level/condition first. Repairs commonly involve replacing the TEHCM/valve body assembly (solenoids are integrated and non-serviceable) and re-learning shift adaptives; the new TEHCM must be programmed to the VIN. Address any fluid overheating cause to prevent recurrence.
On GMT800 Sierra 1500 trucks equipped with the 4L60-E family automatic, a well-known internal failure is cracking or stripping of the reaction sun shell. Owners commonly report sudden loss of reverse, no 2nd gear, no 4th gear, or a truck that starts in 3rd gear after a bang or flare. This is widely documented in transmission rebuild literature, repair databases, and owner reports for GM trucks and SUVs using this transmission.
Diagnosis usually starts with verifying gear loss patterns, checking line pressure, and scanning for ratio/performance codes before condemning the unit. Repair requires transmission removal and overhaul or replacement, typically installing an upgraded hardened sun shell such as the commonly recommended 'Beast' style shell along with inspection of clutches, band, pump, and valve body wear items.
The Active Fuel Management (AFM) and Dynamic Fuel Management (DFM) systems use special hydraulic lifters that collapse to deactivate cylinders for fuel economy. These lifters are prone to premature failure due to poor physical design and inadequate oil flow. Failures can occur as early as 4-digit mileage on newer trucks or 50,000-100,000 miles on older models. When a lifter fails, it can cause catastrophic engine damage requiring complete engine teardown.
Replace all 16 lifters and associated components (camshaft inspection recommended). Install AFM/DFM delete kit to disable cylinder deactivation permanently. Use AFM/DFM disabler device to prevent system activation. Use high-quality synthetic oil and change at 5,000 mile intervals.
High Confidence1,250 owner reportsLast reported by owners Feb 2024Reviewed Feb 2026
GM recalled 2021-2024 Sierra 1500 trucks equipped with the 6.2L L87 V8 because manufacturing defects in the connecting rods and/or crankshaft can cause bearing seizure and catastrophic engine failure. Owners in NHTSA reports describe a knocking or grinding noise developing over days or weeks, then a violent shudder, a bang, and total loss of power — several at highway speed in traffic, some with the engine catching fire. Failures are reported as low as 7,500-22,000 miles. This is by far the dominant complaint theme for the 2024 Sierra 1500: engine-related reports account for roughly half of all filings for the model year. Complaint ODI numbers include 11700648, 11649398, 11680361, 11637614 and many more.
Check your VIN against NHTSA campaign 25V274000. Dealers inspect the engine and repair or replace it as necessary at no charge; owner notification began June 18, 2025. Trucks that pass inspection receive higher-viscosity 0W-40 oil, a new oil fill cap indicating the revised spec, a new oil filter, and updated documentation. Note that owners report long engine-replacement lead times. If you hear any knock, tick, or rumble from the engine — especially under load or during deceleration — stop driving and have it inspected immediately rather than waiting for the recall appointment; continuing to drive turns a bearing repair into a full engine replacement.
P0016 means the crankshaft and Bank 1 intake camshaft are out of sync beyond tolerance. On the 5.3L V8 Sierra 1500 this is a signature failure because of two engine-specific problems: (1) the timing chain stretches over time — accelerated by AFM lifter debris and extended oil-change intervals — retarding cam timing until correlation exceeds threshold; and (2) the cam actuator (VVT) solenoid or phaser sticks. The AFM V8s are also known for oil consumption, and low/dirty oil starves the phasers and clogs solenoid screens, which both triggers P0016 and worsens chain wear. This is more serious than the related P0011: a severely stretched chain can jump a tooth and cause piston-to-valve contact, so continued driving is risky.
Check oil level/condition first — low or sludged oil alone can set it. Use a scan tool to read cam-retard/phaser data. If the timing chain is stretched (confirmed by measuring cam retard or valve-cover inspection), replace the timing chain, guides, tensioner, and cam phaser/sprocket; if only the VVT solenoid is stuck, replace it. Address AFM oil consumption to prevent recurrence.
What you need to diagnose it
The repair instructions explicitly call for reading stored codes. Use a scanner that can read the named code families before choosing a repair.The recommended scanner supports these code families; confirm your exact year, model and module coverage before buying.
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Reading and clearing the code is DIY work. Module replacement or reprogramming is not — most modules are VIN-programmed, so a new one does nothing until a shop codes it to your car. Check for an open recall or service bulletin before buying anything.
Direct injection engines do not spray fuel over the intake valves like port injection systems, allowing carbon deposits from oil and blow-by gases via the PCV system to accumulate on intake valve backs and ports. Over time, this buildup restricts airflow causing performance and efficiency loss. The 5.3L and 6.2L engines with direct injection are susceptible to this issue typically after 60,000-100,000 miles.
Medium Confidence345 owner reportsLast reported by owners Feb 2024Reviewed Feb 2026
P0011 means the Bank 1 intake camshaft is timed more advanced than the ECM commanded — the phaser is stuck/biased advanced. On the Sierra 1500 5.3L/6.2L, the dominant cause is a VVT (camshaft actuator) solenoid whose internal screen has clogged with oil sludge or AFM debris, jamming the plunger so oil pressure to the phaser can't be modulated. GM acknowledges sticking/binding solenoids in PIs such as PIP5130K and PIP5855. Low or incorrect-viscosity oil is a very common trigger, so oil condition is always checked first. Because AFM lifter wear sheds metal into the oil, that debris circulates and clogs the solenoid screens — tying P0011 directly to the trucks' oil-consumption reputation. Drivers report rough running, and in worse cases stalling when slowing to a stop.
Check engine oil level, viscosity, and condition first; an oil/filter change with correct-spec oil sometimes clears it. A proven test is swapping the Bank 1 intake solenoid with another solenoid — if the code follows to P0014/P0021, the solenoid is bad. Replace the VVT/cam actuator solenoid (roughly $40-$90 part). If the phaser or timing chain is worn, the timing set must be replaced.
The 4.8L, 5.3L, and 6.0L Vortec engines used in early GMT800 Sierra trucks place the knock sensors in wells beneath the intake manifold, where water can collect and corrode the sensors or harness. Owners frequently report recurring check-engine lights, timing retard, and reduced power, especially after washing the engine bay or driving in wet conditions. GM issued service information addressing knock sensor corrosion and revised sealing practices.
Diagnosis involves scanning for knock sensor circuit codes, checking freeze-frame data, and inspecting the sensor wells and sub-harness under the intake for moisture or corrosion. Proper repair is replacement of both knock sensors and the harness, cleaning the valley area, and resealing the intake and sensor openings with the updated grommets/sealant procedure to prevent repeat failures.
The electronic brake control module (EBCM) experiences failures causing ABS, traction control, and stability control systems to malfunction. Issues range from warning lights illuminating to complete system failures. The 2023 models have a specific recall for software that may fail to display a warning light when brake fluid loss occurs.
Medium Confidence345 owner reportsLast reported by owners Feb 2024Reviewed Feb 2026
GM recalled 2014-2018 GMC Sierra trucks under NHTSA campaign 19V645000 because the amount of vacuum created by the vacuum pump may decrease over time. The vacuum pump is what gives the Sierra's brake pedal its power assist, so as the vacuum level drops, brake assist decreases. A Sierra owner experiences this as a pedal that takes more effort to push and a truck that needs a longer distance to come to a stop, which NHTSA states increases the risk of a crash. This is a progressive condition rather than a sudden failure - the assist fades as pump output declines. The campaign covers 3,456,719 vehicles in total across all of the GM trucks and SUVs included in the recall; that figure is campaign-wide and is not a count of Sierras.
The remedy is free at any GMC dealer: the dealer reprograms the Electronic Brake Control Module (EBCM). No brake hardware replacement is part of the recall remedy. GM began notifying owners October 8, 2019, and GM's internal number for the campaign is N192268490. If you bought your Sierra used or never received a letter, enter your VIN at nhtsa.gov/recalls to see whether this recall is still open on your truck, then call GMC customer service at 1-800-462-8782 or your dealer to schedule the reprogramming.
Corrosion of steel brake lines is a major safety issue on older Sierra 1500 trucks, especially in salt-belt states. Owners report the brake pedal suddenly dropping to the floor when a rusted line bursts during normal braking, often near the ABS module or along the frame rails. The problem is heavily documented in NHTSA complaints and repair forums for GMT800 trucks and related GM full-size pickups.
Common Symptoms
brake pedal suddenly goes to floor
brake fluid leak under truck
reduced braking performance
ABS warning light may illuminate
visible rust and scaling on brake lines
How to Fix
Inspect all hard brake lines from the master cylinder/ABS module to the rear axle and front calipers, paying close attention to flaking rust and wet spots. Spot repairs may buy time, but many owners end up replacing the full line set with pre-bent stainless or coated steel lines because multiple sections are usually compromised. After replacement, the system must be properly bled, including ABS bleed procedures when needed.
Owners of 2024-2025 Sierra 1500 trucks report the factory rear-view camera image is effectively black in any unlit area. In daylight the picture is sharp; at night the LED reverse lamps are aimed too high and are too dim to light the ground behind the truck, so the camera sensor sees almost nothing beyond a foot or two. NHTSA complaints describe only the red guideline overlay being visible, an adult standing 3-5 ft behind the truck being lit at chest level (a child or a bicycle is invisible), and at least one reported garage-door collision while backing. Dealers repeatedly tell owners the system is 'operating as designed' after checking it in a lit service bay. This is separate from the intermittent black-screen/camera-module dropout fault — here the camera works, but there is no light for it to work with. Complaint ODI numbers include 11703585, 11685671, 11658856, 11648167, 11645362, 11629474, 11627444, 11622143, 11620997, 11614888, 11610906, 11608202, 11601046, 11570814 (2024) and 11707086, 11693732, 11678658, 11664238, 11663238, 11634151 (2025).
Common Symptoms
How to Fix
There is no GM recall or free remedy for the illumination deficiency itself; dealers generally document the camera as operating to specification. Before chasing the camera, verify GM bulletin PIC6566B has been applied (Image Processing Module / Video Processing Module software reset) to rule out a separate software fault. The practical owner fix is to add rear lighting: an LED reverse-light bulb upgrade or an auxiliary rear-facing LED pod wired to the reverse circuit dramatically improves the camera image. Some owners also aim aftermarket bed or hitch-area lights downward. Document repeat dealer visits in writing — several owners have used the repeat-repair record to pursue buyback/lemon claims.
2024-2025 Sierra 1500 owners report the forward collision / automatic emergency braking system commanding hard braking with nothing in the travel lane. Documented triggers include a vehicle legally parked on the shoulder while the truck was travelling 55 mph (speed dropped to about 30 mph with no prior alert), overtaking a tractor-trailer at 70+ mph on a divided highway, and low-speed manoeuvring in parking lots. Two 2025 reports describe adaptive cruise applying the brakes hard enough to cause neck strain. Some trucks display a persistent 'Service Driver Assist System' message alongside the false activations, and others show the opposite failure — AEB not intervening when it should. Rear-end collision exposure is the obvious risk. Complaint ODI numbers include 11705288, 11729845, 11661333, 11616606, 11629735, 11726911, 11730614 (2024) and 11748748, 11695954 (2025).
Common Symptoms
How to Fix
Have the dealer scan for driver-assist DTCs and check for outstanding software updates to the Frontview Camera Module and front radar sensor — a large share of these cases are calibration/software rather than hardware. Confirm the radar emblem area and windshield camera zone are free of ice, mud, aftermarket film, or a bug shield that alters airflow-borne debris patterns; front-end collision repair or windshield replacement without proper static/dynamic ADAS recalibration is a common root cause. If the behaviour persists after recalibration, the Forward Collision Alert sensitivity can be reduced and the AEB system disabled through the vehicle settings menu (note this also disables a genuine safety function). File an NHTSA complaint — this is exactly the ADAS category driving the 2026 recall wave.
A common GMT800 Sierra problem is failure of the in-tank fuel pump module, often from worn pump motors or failed level-sender/module electronics. Owners report long crank, hard starting, loss of power under load, or sudden stall/no-start conditions, especially as mileage climbs. This issue is widely documented in owner forums and complaint databases across 4.3L, 4.8L, 5.3L, and 6.0L trucks.
fuel gauge may act erratically if sender/module is failing
whining noise from fuel tank
How to Fix
Diagnosis usually starts with checking fuel pressure at the rail and verifying pump prime at key-on. Low or unstable pressure, especially after sitting, points to a weak pump or failing module. Repair is replacement of the complete fuel pump module and, ideally, the fuel filter on applicable years; corroded electrical connectors at the tank should also be inspected and replaced if heat-damaged.
A very common GMT800 complaint is sulfur contamination and wear of the fuel level sensor contacts inside the tank module, causing the gauge to read empty, full, or fluctuate unpredictably. Owners often see a low-fuel warning with plenty of fuel in the tank or watch the gauge drop suddenly while driving. GM issued service information and special coverage on many trucks for this exact condition.
Confirm the issue by comparing scan-tool fuel level data and observing whether the sender reading jumps erratically. The usual repair is replacement of the fuel level sensor or, more commonly, the entire fuel pump module assembly because of labor overlap and the age of the pump. Connector condition and ground integrity should also be checked during service.
GM recalled certain 2026 Sierra 1500 trucks built with four-wheel drive or all-wheel drive because a component was omitted from the drivetrain transfer case during assembly. The omission can allow the front and/or rear wheels to lock up suddenly, with no warning to the driver — a loss-of-control event at any speed. NHTSA campaign 26V289000 (GM internal number N262557620) was filed May 7, 2026 and carries a DO NOT DRIVE advisory, which GM issues only for the most severe defects. The same campaign covers 2026 Silverado 1500, Suburban, Tahoe, Yukon, Yukon XL, Escalade and Escalade ESV, plus certain 2015-2020 full-size SUVs. This is a build/assembly defect, not a wear item, so an affected truck can fail at delivery mileage.
Common Symptoms
How to Fix
Do not drive the vehicle until the recall is completed. Check your VIN against NHTSA campaign 26V289000. Dealers will inspect the transfer case and replace the complete transfer case assembly if the component is missing, free of charge. Owner notification letters were mailed May 18, 2026. GMC customer service: 1-800-462-8782. If the truck must be moved, have it towed.
2024-2025 Sierra 1500 owners report the power MultiPro tailgate unlatching and falling open on its own, most often while driving, after hitting a bump or rain gutter, or after a car wash. Nobody presses the release; several owners returned to the truck to find the gate resting against a garage door. Documented consequences in NHTSA reports include the tailgate striking a towed trailer's jack on a left turn, cargo falling out onto the roadway, and repeated cosmetic damage to the top edge of the gate. Forum diagnosis points to water entering through two drain holes in the handle cavity and shorting the tailgate release switch, which is why the fault is strongly weather-correlated. GM recalled 2021-2023 Sierra and the Sierra HD (2024) for unlatching tailgates but has not extended coverage to the 2024-2025 1500, and owners report their VINs falling outside the campaign. Complaint ODI numbers include 11681958, 11675633, 11657356, 11642113, 11637129, 11632101, 11631949, 11591659, 11581039 (2024) and 11670408 (2025).
Common Symptoms
How to Fix
Have the dealer inspect and replace the tailgate release switch and, if corroded, the tailgate control/latch module; the connector should be re-sealed with dielectric grease. Owners have had lasting success sealing the two drain holes in the top of the plastic handle-cavity trim so water cannot reach the switch. As an interim safety measure while towing or hauling loose cargo, pull the tailgate release fuse or have the dealer disable the power-release feature. Keep a written repair record — GM has paid for consequential damage on a case-by-case basis, and this may yet expand into a 1500-series campaign.
The infotainment system experiences intermittent complete audio loss affecting stereo, turn signals, and safety warning sounds. The audio system may randomly go to maximum volume and cannot be controlled. OTA software updates have caused additional issues including erratic blinker tones, constant reboots while driving, and frozen camera screens.
Turn signal and safety warning sounds stop working
Infotainment screen freezes or reboots while driving
Backup camera display freezes or goes black
Bluetooth connectivity issues
How to Fix
Perform hard reset by disconnecting battery for 30 minutes. Software update at dealership. Replace infotainment head unit/radio module. Replace audio amplifier for Bose systems.
Medium Confidence456 owner reportsLast reported by owners Feb 2024Reviewed Feb 2026
Distinct from the night-visibility complaint, 2024-2025 Sierra 1500 owners report the entire camera suite — rear, front, side-mirror and bird's-eye surround views — cutting out intermittently and displaying a black screen with crossed-out camera icons. The pattern owners describe is thermal: the cameras work when the truck is cold and after it has sat, then fail once the vehicle has been running or driven for a while, pointing at the Video Processing Module / Image Processing Module. Gridline overlays also drop out independently. Repeat dealer visits are common (one owner reported five visits and a full infotainment replacement without resolution, another reported a third camera module replacement); at least one report describes a garage-door collision when the display went blank while reversing. Complaint ODI numbers include 11746275, 11721762, 11693556, 11620174 (2024) and 11684291 (2025).
Common Symptoms
How to Fix
Have the dealer apply GM bulletin PIC6566B, which addresses rear-camera black-screen faults across current GM trucks and directs a reset/reprogram of the Image Processing Module (IPM) or Video Processing Module (VPM); many cases are a software anomaly rather than a hardware fault. If the fault returns after the reset and follows the thermal pattern, insist on VPM/IPM replacement rather than repeated camera swaps, and have the technician check the coaxial camera harness connectors for backed-out or corroded pins. Because a functioning backup camera is a federally mandated safety feature, escalate to GMC customer assistance (1-800-462-8782) with a repair-attempt log if the dealer cannot resolve it.
A recurring 2025 Sierra 1500 electrical fault kills every audio output in the cabin at once. Owners start the truck and there is no radio, no turn-signal tick, no chime for hazard flashers, no Apple CarPlay audio, and — critically — no audible forward-collision, rear-cross-traffic or lane-departure warning. The cabin is completely silent. The condition is intermittent, appears at start-up, and can persist for hours; a restart sometimes clears it. Because the visual and audible warning channels are decoupled, a driver can be unaware the alerts are muted until a warning is needed. Multiple owners report three or more dealer repair attempts without resolution, including amplifier and radio-module replacements. Complaint ODI numbers include 11734260, 11695335, 11683187 and 11688990.
Have the dealer scan the GMLAN/serial data bus for module communication faults and check for updated software for the radio (RCM) and the external audio amplifier — most reports point at the amplifier or the radio control module dropping off the bus at start-up rather than a speaker fault. Verify the amplifier ground and connector, and check whether an over-the-air update preceded the onset. If audio is lost, treat the truck as having no audible safety alerts and rely on the visual warnings in the cluster and head-up display until repaired. Document each occurrence with date and mileage — repeat-repair records are the leverage for escalation, and this fault sits squarely in the electrical category driving current GM recall activity.
GMT900 Sierra trucks are well known for failing door lock actuators, often starting with one door that unlocks weakly or only works intermittently before additional doors fail. Owners report the key fob cycling the locks while one or more doors remain stuck, requiring manual operation from inside. The issue is heavily documented across GM full-size truck forums and complaint records.
Common Symptoms
door will not lock or unlock with key fob
weak buzzing from inside door
intermittent power lock operation
one or more doors stuck locked
manual lock works but power lock does not
How to Fix
Diagnosis involves confirming power and ground at the latch/actuator assembly and ruling out broken door-jamb wiring or BCM command issues. The usual fix is replacement of the failed actuator or latch-actuator assembly in the affected door, followed by checking all doors because multiple actuators often fail within a similar time period.
2003-2007 Classic-era Sierra trucks are well known for instrument cluster gauge failures caused by defective stepper motors and, in some cases, backlighting issues. Speedometer, tachometer, oil pressure, fuel, voltage, and coolant gauges can stick, read wildly high or low, or stop moving entirely. The problem became widespread enough that GM issued a special coverage adjustment on many trucks and SUVs using the same cluster design.
Common Symptoms
speedometer reads 0 or pegs past 120 mph
fuel gauge inaccurate
oil pressure gauge stuck high or low
tachometer inoperative
intermittent or failed cluster backlighting
warning chimes with incorrect gauge readings
How to Fix
Verify actual vehicle data with a scan tool or GPS speed app to confirm the cluster is inaccurate rather than the sending unit. Repair is typically cluster removal and professional rebuild with updated stepper motors and bulbs, or replacement with a remanufactured unit programmed for the vehicle. If only one gauge is wrong, the whole cluster is still usually rebuilt because the remaining motors often fail later.
P0430 is the Bank 2 counterpart to P0420 and, on the Sierra 1500 V8, points to the driver-side (Bank 2) catalytic converter falling below efficiency threshold. The mechanism is identical to Bank 1: the rear O2 sensor voltage begins mirroring the front sensor, so the ECM concludes that bank's cat can no longer store/release oxygen. The specific pattern on these trucks is that the underlying killer is usually AFM-related oil consumption or a lazy/aged rear O2 sensor rather than a defective converter out of the box. Owners commonly report P0430 (or both P0420 and P0430) returning even after installing new aftermarket converters — a well-documented frustration on GM-Trucks and SilveradoSierra forums — because the root cause (oil burning, exhaust leak, or a slow O2 sensor) was never corrected.
Confirm with a smoke/leak check and O2 sensor live-data (rear sensor should be lazy/flat, not switching). Rule out driver-side manifold bolt leaks. Replace a lazy Bank 2 rear O2 sensor first if indicated. If the converter is confirmed inefficient, fit an OEM/CARB-compliant direct-fit unit and fix any oil consumption; expect aftermarket cats to re-trigger if the AFM oil burn persists.
On the 5.3L V8 Sierra 1500, P0420 sets when the downstream (post-cat) O2 sensor tracks the upstream sensor too closely, meaning the Bank 1 catalytic converter is no longer scrubbing exhaust efficiently. The distinctive part on these trucks: the converter frequently dies prematurely from an upstream cause rather than age. Active Fuel Management (AFM) V8s burn oil past the lifters/rings, and that oil ash slowly poisons the catalyst substrate. GM TSB #16-NA-111 also documents a lesser-known trigger: a poor air-filter-housing seal lets abrasive dirt bypass the filter, wearing the O2 sensors and clogging the cat from the inside. Broken exhaust manifold bolts (a chronic GM V8 issue) create leaks that mimic P0420. Aftermarket cats have a poor track record here and often re-trigger the code within months.
Do not blindly replace the converter. First scan for exhaust leaks (check manifold bolts), inspect the air-filter housing per TSB 16-NA-111, and check upstream/downstream O2 sensor operation with live data. Address AFM oil consumption if present. If the converter is genuinely spent, install an OEM or high-quality direct-fit unit and complete the heat-cycle break-in before the monitor re-runs.
P0442 on the Sierra 1500 is a small EVAP leak detected during the ECM's key-off/idle vacuum test. On these trucks the two most common real-world causes are a loose, worn, or cracked gas cap seal (the cheapest fix and always the first check) and — a documented GM issue (TSB 15-NA-019) — the fuel tank filler vent hose connector cracking, which allows vapor to escape and sets P0442 (and sometimes P0455). The vent hose fracture is addressed by replacing the vent hose assembly (part No. 22802073 on 2013-2015 models). The EVAP purge valve (engine bay) and vent solenoid (near the tank) can also weep. Drivers often notice a faint fuel odor and the CEL, with no drivability change.
Start with the gas cap — inspect the seal and tighten/replace with OEM. If the code persists, perform a smoke test to pinpoint the leak; inspect the fuel filler vent hose connector for cracks and replace the vent hose assembly if fractured. Replace the purge or vent solenoid if the smoke test isolates it there.
P0455 indicates a large (gross) EVAP leak — the ECM cannot pull or hold vacuum in the evaporative system at all. On the Sierra 1500 the classic causes are a completely missing/unsealed gas cap, a stuck-open or failed EVAP vent solenoid (mounted under the truck near the fuel tank/spare tire, where it's exposed to road spray, dirt, and corrosion), and a cracked or disconnected vapor/vent hose. Because the vent solenoid sits at the canister under the bed, water intrusion and corrosion cause it to stick open, which the ECM reads as a wide-open system; a tell-tale symptom is the fuel nozzle repeatedly clicking off during refueling. The filler vent hose connector fracture noted in GM literature can also escalate to P0455. Symptom-wise the driver usually sees only the CEL, sometimes a fuel smell, and no performance loss.
Confirm the gas cap is present and sealing. Smoke-test the EVAP system to find the large leak. The most common repair on these trucks is replacing the under-body EVAP vent solenoid/valve at the canister; also inspect and replace cracked vapor lines and the fuel filler vent hose. Clear codes and run the EVAP monitor to confirm.
The upper intermediate steering shaft develops excessive wear causing a pronounced clunking noise when turning the steering wheel or going over bumps. The issue is caused by wear in the shaft's universal joints or the plastic bushing near the firewall. GM has redesigned the part multiple times but the problem persists.
Clunking noise when turning steering wheel at low speeds
Clunk or rattle when going over bumps
Play or looseness felt in steering wheel
Creaking noise from steering column area
How to Fix
Replace upper intermediate steering shaft with redesigned part (GM part number 84105918 or later). Lubricate shaft U-joints (temporary fix). Replace plastic bushing near firewall. DIY hose clamp fix to tighten shaft above plastic bearing.
High Confidence678 owner reportsLast reported by owners Feb 2024Reviewed Feb 2026
Front wheel hub bearing assemblies on Sierra 1500 trucks commonly wear out, especially on 4WD models and trucks used with larger tires or in rough conditions. Owners report humming or growling that changes with speed, looseness in the front wheel, and in some cases ABS warnings or low-speed ABS activation because the wheel speed sensor is integrated into the hub. This is a frequent repair item across both GMT800 and GMT900 generations.
Diagnosis involves checking for wheel play with the tire off the ground, listening for bearing noise during road tests, and comparing wheel speed sensor data if ABS symptoms are present. Repair is replacement of the affected hub assembly, and many owners replace both sides if mileage is high. Corrosion at the sensor mounting surfaces and wiring damage should also be addressed to prevent repeat ABS issues.
The A/C compressor is prone to premature failure due to faulty welds, insufficient lubrication, or internal mechanical failure. When the compressor fails catastrophically, metal debris contaminates the entire A/C system requiring replacement of multiple components. The A/C clutch can also fail independently, preventing compressor engagement.
Common Symptoms
A/C blows warm air
A/C works intermittently
Unusual noise when A/C is engaged
A/C clutch not engaging
Visible refrigerant leak
A/C cools then gradually warms up
How to Fix
Replace A/C compressor with revised GM part. Flush A/C system and replace expansion valve, receiver/dryer, and condenser if compressor failed catastrophically. Replace A/C clutch assembly. Repair refrigerant leaks and recharge system.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
A/C Compressor
Cross-ref471-1021
Fitment confirmed against the ShowMeTheParts catalog for this vehicle's year and engine.
Medium Confidence567 owner reportsLast reported by owners Feb 2024Reviewed Feb 2026
On the Sierra 1500, P0128 means the coolant did not reach the expected regulating temperature within the time/airflow the ECM predicted — almost always a thermostat stuck open (or partly open) so the engine runs too cool. The GM thermostat on the 5.3L/6.2L is integrated into a plastic housing on the engine, and the common failure is the thermostat losing its ability to close, letting coolant circulate continuously. Drivers notice the temp gauge sitting low, weak or slow-to-warm cabin heat (especially in winter), and worse fuel economy because the ECM stays in open-loop enrichment longer. A stuck-open thermostat is by far the most frequent cause; a failed/biased coolant temperature sensor is the secondary suspect and should be verified with live data before parts are thrown at it.
Verify actual coolant temperature with a scan tool vs. the gauge to separate a bad ECT sensor from a bad thermostat. If the engine won't reach ~195-210°F, replace the thermostat (and housing/gasket, commonly sold as an assembly) with an OEM-spec unit and refill/bleed the cooling system. Replace the ECT sensor if data shows an implausible reading.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
Engine Coolant Thermostat
Cross-refTHRGM-0002
Fitment confirmed against the ShowMeTheParts catalog for this vehicle's year and engine.
Sierra owners across both GMT800 and GMT900 generations frequently report small electric HVAC actuators stripping internal gears or losing calibration. The result is a repetitive clicking or tapping noise from the dash, air stuck on defrost or floor, or one side blowing hot while the other blows cold. This is one of the most common non-drivetrain complaints on these trucks and is heavily documented in owner forums and repair databases.
Diagnosis is done by commanding HVAC modes and temperatures while listening for actuator chatter and verifying door movement with a scan tool or visual inspection where accessible. Repair involves replacing the failed mode, blend, or recirculation actuator and then performing HVAC recalibration by fuse pull or scan-tool procedure depending on year and system configuration.
Owners of 2007-2013 Sierra 1500 trucks commonly report the upper dash cracking near the passenger airbag area and around defrost vents, especially in hot climates. While primarily a cosmetic and rattling issue, some owners also complain that broken plastic edges and loose pieces worsen over time. The problem is widely discussed in owner communities for GMT900 GM trucks and appears repeatedly in complaint databases.
Common Symptoms
cracked dashboard
rattles from dash area
broken plastic near passenger airbag
sun-damaged interior trim
loose dash pieces
How to Fix
Inspect for cracks around the passenger-side airbag opening, center speaker area, and defrost vent corners. Repair options include replacing the dash pad, installing a molded dash cap, or using plastic repair methods for minor cracks; replacement is the most durable but also the most labor-intensive and expensive option.
General Motors LLC (GM) is recalling certain 2021-2024 Cadillac Escalade and Escalade ESV, Chevrolet Silverado 1500, Suburban, and Tahoe, GMC Sierra 1500, Yukon, and Yukon XL vehicles equipped with a 6.2L V8 gas engine. The connecting rod and/or crankshaft engine components may have manufacturing defects that can lead to engine damage and engine failure.
Campaign #25V27400024/04/2025
EXTERIOR LIGHTING:BRAKE LIGHTS
General Motors (GM) has decided that certain 2022 model year Chevrolet Silverado, and GMC Sierra vehicles equipped with an accessory sport bar. The accessory sport bar contains a high-mounted brake light that may not function. In addition, it may block the vehicle's existing high-mounted brake light. As such, these vehicles may fail to conform to Federal Motor Vehicle Safety Standard (FMVSS) number 108, "lamps, reflective devices, and associated equipment."
Campaign #22V46300030/06/2022
POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE
General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel engines. The transmission control valve may fail and cause the rear wheels to lock-up.
Reliability varies across model years of the GMC Sierra 1500. Based on documented issues, problems are most commonly reported in earlier model years. Au7o recommends checking the specific known issues for your target year before purchasing, and having a pre-purchase inspection performed by a qualified mechanic. Our known issues database covers the 1999-2026 GMC Sierra 1500 with 35 documented issues documented across 4,765+ owner reports.
What is the 2014-2023 GMC Sierra 1500 AFM/DFM Lifter Collapse and Failure?
The Active Fuel Management (AFM) and Dynamic Fuel Management (DFM) systems use special hydraulic lifters that collapse to deactivate cylinders for fuel economy. These lifters are prone to premature failure due to poor physical design and inadequate oil flow. Failures can occur as… Repairs typically run $4,000-$8,000. Severity: high.
What is the 2015-2023 GMC Sierra 1500 8-Speed/10-Speed Transmission Torque Converter Shudder?
The 8L90 8-speed and 10L80/10L90 10-speed automatic transmissions experience shuddering during light throttle acceleration, particularly at highway speeds between 35-60 mph. The issue is caused by the torque converter lock-up clutch slipping and chattering. Harsh shifts between g… Repairs typically run $150-$4,500. Severity: high.
What is the 2014-2023 GMC Sierra 1500 Electronic Brake Control Module Failure?
The electronic brake control module (EBCM) experiences failures causing ABS, traction control, and stability control systems to malfunction. Issues range from warning lights illuminating to complete system failures. The 2023 models have a specific recall for software that may fai… Repairs typically run $150-$1,500. Severity: high.
What is the 2014-2015 GMC Sierra 1500 Transfer Case Unintended Shift to Neutral?
An electrical signal short in the transfer case can cause it to shift to neutral without driver input while driving. This results in sudden loss of power to the wheels creating a serious safety hazard, particularly at highway speeds or when towing. Repairs typically run $0-$0. Severity: high.
What is the 2014-2018 GMC Sierra 1500 NHTSA Recall 19V645000: Declining Vacuum Pump Output Reduces Power Brake Assist?
GM recalled 2014-2018 GMC Sierra trucks under NHTSA campaign 19V645000 because the amount of vacuum created by the vacuum pump may decrease over time. The vacuum pump is what gives the Sierra's brake pedal its power assist, so as the vacuum level drops, brake assist decreases. A… Severity: high.
What is the 2026 GMC Sierra 1500 Missing Transfer Case Component Can Lock the Front or Rear Wheels Without Warning (Recall 26V289000 — Do Not Drive)?
GM recalled certain 2026 Sierra 1500 trucks built with four-wheel drive or all-wheel drive because a component was omitted from the drivetrain transfer case during assembly. The omission can allow the front and/or rear wheels to lock up suddenly, with no warning to the driver — a… Repairs typically run $0-$0. Severity: high.
What is the 2024-2025 GMC Sierra 1500 MultiPro Tailgate Drops Open By Itself While Driving — Water Intrusion at the Handle-Cavity Release Switch?
2024-2025 Sierra 1500 owners report the power MultiPro tailgate unlatching and falling open on its own, most often while driving, after hitting a bump or rain gutter, or after a car wash. Nobody presses the release; several owners returned to the truck to find the gate resting ag… Repairs typically run $250-$950. Severity: high.
What is the 2024-2025 GMC Sierra 1500 10L80/10L90 10-Speed Valve Body Failure — Loss of Reverse, Limp Mode, and Year-Long Parts Backorder?
2024-2025 Sierra 1500 trucks with the 10-speed automatic (5.3L L84, 6.2L L87 and 3.0L Duramax LZ0) are failing at very low mileage with a stuck valve-body solenoid. Symptoms: a 'Service Transmission' or 'Service Transmission — Unable to Shift Soon' message, sudden hard/slamming s… Repairs typically run $900-$6,500. Severity: high.
What is the 2024-2025 GMC Sierra 1500 Rear-View Camera Unusable at Night — Reverse Lamps Do Not Illuminate the Camera's Field of View?
Owners of 2024-2025 Sierra 1500 trucks report the factory rear-view camera image is effectively black in any unlit area. In daylight the picture is sharp; at night the LED reverse lamps are aimed too high and are too dim to light the ground behind the truck, so the camera sensor… Repairs typically run $80-$400. Severity: high.
What is the 2024 GMC Sierra 1500 6.2L L87 V8 Connecting Rod and Crankshaft Failure — Sudden Loss of Propulsion (Recall 25V274000)?
GM recalled 2021-2024 Sierra 1500 trucks equipped with the 6.2L L87 V8 because manufacturing defects in the connecting rods and/or crankshaft can cause bearing seizure and catastrophic engine failure. Owners in NHTSA reports describe a knocking or grinding noise developing over d… Repairs typically run $0-$15,000. Severity: high.
What is the 2007-2021 GMC Sierra 1500 P0016 — Crank/Cam Correlation Fault from Stretched Timing Chain on 5.3L AFM V8?
P0016 means the crankshaft and Bank 1 intake camshaft are out of sync beyond tolerance. On the 5.3L V8 Sierra 1500 this is a signature failure because of two engine-specific problems: (1) the timing chain stretches over time — accelerated by AFM lifter debris and extended oil-cha… Repairs typically run $150-$1,800. Severity: high.
What is the 2007-2018 GMC Sierra 1500 P0700 — Transmission Fault Flag from Failing 6L80/6L90 Internal TEHCM?
P0700 itself is only a flag: the Transmission Control Module has stored one or more transmission faults and is requesting the MIL. On Sierra 1500s with the 6L80 (and 6L90 on heavier variants) 6-speed automatic, the notable design issue is that the TCM is integrated into the valve… Repairs typically run $600-$2,500. Severity: high.
What is the 2000-2007 GMC Sierra 1500 4L60-E / 4L65-E Sun Shell Failure Causing Loss of Reverse and 2nd/4th Gear?
On GMT800 Sierra 1500 trucks equipped with the 4L60-E family automatic, a well-known internal failure is cracking or stripping of the reaction sun shell. Owners commonly report sudden loss of reverse, no 2nd gear, no 4th gear, or a truck that starts in 3rd gear after a bang or fl… Repairs typically run $1,800-$3,500. Severity: high.
What is the 2000-2007 GMC Sierra 1500 Fuel Pump Module Failure Causing No-Start or Stalling?
A common GMT800 Sierra problem is failure of the in-tank fuel pump module, often from worn pump motors or failed level-sender/module electronics. Owners report long crank, hard starting, loss of power under load, or sudden stall/no-start conditions, especially as mileage climbs. Repairs typically run $500-$1,200. Severity: high.
What is the 1999-2007 GMC Sierra 1500 Rusting Brake Lines Leading to Fluid Loss and Sudden Brake Failure?
Corrosion of steel brake lines is a major safety issue on older Sierra 1500 trucks, especially in salt-belt states. Owners report the brake pedal suddenly dropping to the floor when a rusted line bursts during normal braking, often near the ABS module or along the frame rails. Th… Repairs typically run $800-$2,500. Severity: high.
What is the 2014-2018 GMC Sierra 1500 Intermediate Steering Shaft Clunk?
The upper intermediate steering shaft develops excessive wear causing a pronounced clunking noise when turning the steering wheel or going over bumps. The issue is caused by wear in the shaft's universal joints or the plastic bushing near the firewall. GM has redesigned the part… Repairs typically run $50-$600. Severity: medium.
What is the 2014-2020 GMC Sierra 1500 A/C Compressor and Clutch Failure?
The A/C compressor is prone to premature failure due to faulty welds, insufficient lubrication, or internal mechanical failure. When the compressor fails catastrophically, metal debris contaminates the entire A/C system requiring replacement of multiple components. The A/C clutch… Repairs typically run $500-$2,500. Severity: medium.
What is the 2019-2023 GMC Sierra 1500 Infotainment System Audio Loss and Malfunction?
The infotainment system experiences intermittent complete audio loss affecting stereo, turn signals, and safety warning sounds. The audio system may randomly go to maximum volume and cannot be controlled. OTA software updates have caused additional issues including erratic blinke… Repairs typically run $0-$2,500. Severity: medium.
What is the 2014-2023 GMC Sierra 1500 Direct Injection Carbon Buildup on Intake Valves?
Direct injection engines do not spray fuel over the intake valves like port injection systems, allowing carbon deposits from oil and blow-by gases via the PCV system to accumulate on intake valve backs and ports. Over time, this buildup restricts airflow causing performance and e… Repairs typically run $400-$800. Severity: medium.
What is the 2007-2018 GMC Sierra 1500 P0430 — Catalyst Efficiency Bank 2 (Driver-Side) Converter Failure on 5.3L V8?
P0430 is the Bank 2 counterpart to P0420 and, on the Sierra 1500 V8, points to the driver-side (Bank 2) catalytic converter falling below efficiency threshold. The mechanism is identical to Bank 1: the rear O2 sensor voltage begins mirroring the front sensor, so the ECM concludes… Repairs typically run $400-$1,500. Severity: medium.
