According to Au7o's analysis of 650+ owner reports, the 1999-2004 Chrysler 300M has 4 documented known issues, with 2 rated critical. The most serious are 3.5L V6 Engine Oil Sludge and Consumption ($50-$4,500 repair) and 42LE Automatic Transmission Failure ($200-$3,500 repair). The most commonly reported issue is 3.5L V6 Engine Oil Sludge and Consumption with 250 owner reports. Across all issues with published estimates, repair costs range from $50 to $4,500. DIY maintenance guides at au7o.io.
The 3.5L SOHC V6 in the 300M is susceptible to oil sludge formation, though less severely than the 2.7L. The high-performance tuning of the 3.5L in the 300M generates more heat than in other applications, and the oil drain-back passages in the heads can become restricted by sludge over time. Oil consumption of 1 quart per 1,000-2,000 miles is commonly reported. The issue is exacerbated by extended oil change intervals and conventional oil use. While not as catastrophic as the 2.7L, the sludge can lead to lifter noise, oil pressure loss, and eventually bearing damage if ignored.
Start by verifying oil consumption and sludge severity: inspect under the oil fill cap/valve covers, check hot idle oil pressure with a mechanical gauge, listen for valvetrain noise, and perform a compression/leak-down test to rule out worn rings or valve seals. If sludge is moderate, remove the valve covers and oil pan to manually clean sludge, clear the cylinder head drain-back passages, replace the PCV valve, and refill with the correct viscosity full-synthetic oil plus a quality filter; if oil pressure is low, inspect/replace the oil pump pickup tube and screen, and repair bearing damage as needed. Engines with persistent consumption may also need valve stem seals or internal engine work, while severe sludge may justify replacing the engine rather than attempting repeated flushes, which can dislodge debris and worsen oil starvation. Typical costs range from about $300-$700 for inspection, cleaning, PCV service, and fresh oil, $800-$1,800 if oil pan/valve cover removal and pickup cleaning are required, and $2,500-$5,000+ for major internal repair or engine replacement.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
PCV Valve
Cross-refPC272
Fitment confirmed against the ShowMeTheParts catalog for this vehicle's year and engine.
High Confidence250 owner reportsLast reported by owners Feb 2026Reviewed Feb 2026
Community reported
220 owners
The 42LE 4-speed automatic transmission in the 300M is prone to premature failure, including solenoid pack issues, torque converter clutch failure, and internal clutch pack wear. The high torque output of the 3.5L V6 stresses the transmission beyond its design limits. Harsh shifting, slipping, and limp mode are common symptoms. The transmission is shared with the Intrepid, Concorde, and LHS, and the failure patterns are identical across all platforms. The solenoid pack and connector are the most common failure points.
High Confidence220 owner reportsLast reported by owners Feb 2026Reviewed Feb 2026
Community reported
180 owners
The power steering rack on the 300M develops leaks from the rack seals, typically on the driver's side inner tie rod boot area. Power steering fluid leaks onto the subframe and can contaminate the front motor mount. The rack seal design is prone to failure due to heat exposure from the engine and exhaust proximity. Symptoms include low power steering fluid, groaning noise during turns, and stiff steering. The leak typically starts as a slow seep and progressively worsens. A full rack replacement is usually required as seal-only kits have poor success rates.
Common Symptoms
Power steering fluid leak visible under vehicle
Groaning or whining noise during turns
Power steering fluid level dropping
Stiff steering, especially at low speeds
Wet or oily inner tie rod boots
How to Fix
Confirm the leak by cleaning the rack, filling the reservoir with the correct ATF+4 power steering fluid, and inspecting the driver-side inner tie rod boot, pressure/return line fittings, and pump area while the steering is turned lock-to-lock. If fluid is coming from inside the boot or rack end seals, replace the complete steering rack assembly rather than attempting a seal repair, then install new rack bushings/O-rings as needed, transfer or replace the outer tie rod ends if worn, refill and bleed the system, and perform a front-end alignment. Inspect the front motor mount and subframe bushings for fluid damage and replace any softened rubber components. Typical repair cost is about $700-$1,300 depending on rack brand, labor time, and whether tie rods, lines, or mounts are also replaced.
High Confidence180 owner reportsLast reported by owners Feb 2026Reviewed Feb 2026
The power steering pump develops a whining noise and leaks fluid from the shaft seal or reservoir. The whine is most noticeable at low speed turns and on cold mornings. Low fluid from leaks accelerates pump wear.
Replace power steering pump and flush the system with fresh ATF+4 (Chrysler uses ATF as power steering fluid). Check all hoses and the rack and pinion for leaks. Use only Mopar-approved fluid.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
Power Steering Pump
Cross-ref21-5410
Fitment confirmed against the ShowMeTheParts catalog for this vehicle's year and engine.
SABERSPORT IS RECALLING 16,270 COMBINATION CORNER AND BUMPER LAMP ASSEMBLIES OF VARIOUS PART NUMBERS SOLD FOR USE AS AFTERMARKET EQUIPMENT FOR VARIOUS PASSENGER VEHICLES. THESE HEADLAMPS FAIL TO CONFORM TO THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 108, "LAMPS, REFLECTIVE DEVICES, AND ASSOCIATED EQUIPMENT." THESE LAMPS DO NOT CONTAIN THE REQUIRED AMBER SIDE REFLECTORS.
Campaign #09E01200007/04/2009
LATCHES/LOCKS/LINKAGES:HOOD:LATCH
ON CERTAIN PASSENGER VEHICLES, AN INTERNAL HOOD LATCH COMPONENT MAY HAVE BEEN MANUFACTURED WITH A CRACK, WHICH COULD PROPAGATE AND BREAK, ALLOWING THE PRIMARY/SECONDARY LATCH SPRING TO DISENGAGE.
Campaign #03V33200008/09/2003
SEATS:FRONT ASSEMBLY:RECLINER
ON CERTAIN PASSENGER VEHICLES, SEAT BACK RECLINER BOLT BREAKAGE CAN OCCUR RESULTING IN THE SEAT BACK RECLINING UNEXPECTEDLY.
Campaign #03V03500005/02/2003
STRUCTURE:FRAME AND MEMBERS
VEHICLE DESCRIPTION: CERTAIN PASSENGER VEHICLES (NON-SUNROOF ONLY) FAIL TO COMPLY WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 201, "OCCUPANT PROTECTION IN INTERIOR IMPACT."
Campaign #01V27300002/08/2001
CHILD SEAT
VEHICLE DESCRIPTION: CERTAIN PASSENGER VEHICLES, PICKUP TRUCKS AND SPORT UTILITY VEHICLES FAIL TO COMPLY WITH THE REQUIREMENTS OF FMVSS NO. 225, "CHILD RESTRAINT ANCHORAGE SYSTEMS." SOME OF THE OWNER'S MANUALS FOR THESE VEHICLES ARE MISSING INSTRUCTIONS THAT PROVIDE A STEP-BY-STEP PROCEDURE, INCLUDING DIAGRAMS, FOR PROPERLY ATTACHING A CHILD RESTRAINT SYSTEM'S TETHER STRAP TO THE TETHER ANCHORAGE.
According to Au7o's analysis of 650+ owner reports, the 1999-2004 Chrysler 300M has 4 documented issues. The most frequently reported are: 3.5L V6 Engine Oil Sludge and Consumption, 42LE Automatic Transmission Failure, Power Steering Rack Leak. Of these, 2 are rated critical and should be addressed promptly.
Is the Chrysler 300M reliable?
The 1999-2004 Chrysler 300M has 4 known issues documented across 650+ owner reports. 2 issues are rated critical: 3.5L V6 Engine Oil Sludge and Consumption and 42LE Automatic Transmission 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 Chrysler 300M problems?
Repair costs for known Chrysler 300M issues range from $50 to $4,500, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, 3.5L V6 Engine Oil Sludge and Consumption, typically costs $50-$4,500 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What year Chrysler 300M is the most reliable?
Reliability varies across model years of the Chrysler 300M. 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 1999-2004 Chrysler 300M with 4 documented issues documented across 650+ owner reports.
What is the 1999-2004 Chrysler 300M 3.5L V6 Engine Oil Sludge and Consumption?
The 3.5L SOHC V6 in the 300M is susceptible to oil sludge formation, though less severely than the 2.7L. The high-performance tuning of the 3.5L in the 300M generates more heat than in other applications, and the oil drain-back passages in the heads can become restricted by sludg… Repairs typically run $50-$4,500. Severity: high.
What is the 1999-2004 Chrysler 300M 42LE Automatic Transmission Failure?
The 42LE 4-speed automatic transmission in the 300M is prone to premature failure, including solenoid pack issues, torque converter clutch failure, and internal clutch pack wear. The high torque output of the 3.5L V6 stresses the transmission beyond its design limits. Harsh shift… Repairs typically run $200-$3,500. Severity: high.
What is the 1999-2004 Chrysler 300M Power Steering Rack Leak?
The power steering rack on the 300M develops leaks from the rack seals, typically on the driver's side inner tie rod boot area. Power steering fluid leaks onto the subframe and can contaminate the front motor mount. The rack seal design is prone to failure due to heat exposure fr… Repairs typically run $400-$900. Severity: medium.
What is the 1999-2004 Chrysler 300M Power Steering Pump Whine and Leak?
The power steering pump develops a whining noise and leaks fluid from the shaft seal or reservoir. The whine is most noticeable at low speed turns and on cold mornings. Low fluid from leaks accelerates pump wear. Repairs typically run $200-$500. Severity: medium.
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.
