P0730: How to Diagnose & Fix — Incorrect Gear Ratio
145 vehicles · 32 makes · $5-$20,000 repair
How to diagnose and fix P0730: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Ford Focus · 2012–2018
The DPS6 PowerShift 6-speed dual-clutch automated transmission fitted to 2012-2018 Ford Focus (and 2011-2019 Fiesta) is widely considered one of the worst transmission designs in modern automotive history. The dry dual-clutch design was fundamentally unsuited for stop-and-go driving, producing violent shuddering during low-speed acceleration, hesitation when pulling away from stops, unexpected surging, and abrupt harsh shifts. Ford knew of the defects from the start but concealed them and continued selling vehicles. Multiple class action lawsuits resulted in settlements covering 2012-2016 models (expanded to 2017-2018). Ford issued dozens of TSBs and software reflashes that repeatedly failed to fix the underlying mechanical problem. The TCM (Transmission Control Module) failures are a distinct but related issue. Repair options include clutch replacement (temporary fix), TCM reprogramming, or complete transmission replacement.
Common Symptoms
- Violent shuddering or juddering when accelerating from a stop
- Transmission hesitates or refuses to move in Drive for 1-3 seconds
- Unexpected lurch forward when releasing brakes at low speed
- Grinding or clunking between gear changes
- Transmission surging and jerking during low-speed driving
- Vehicle bucks and shakes at 15-35 mph (clutch slip zone)
- Transmission warning light or "Transmission Fault" message
- Loss of drive in one or both gears
- Delayed engagement from Park to Drive
How to Fix
Check fordtransmissionsettlement.com for class action settlement eligibility. Ford's warranty extended to cover repeated repairs. Updated clutch service parts: Focus uses F1FZ-7B546-B clutch (replaces BV6Z-7B546-F). TCM repair/replacement per TSB 16-0109. Software recalibration via IDS tool at dealer. For definitive fix: remanufactured DPS6 transmission. Many owners chose to pursue buyback via state Lemon Laws. Latest settlements include 2017-2018 models under separate class action.
Sources for this issue (2)
Ford Mustang · 2015–2023
The MT82 6-speed manual transmission is notorious for multiple issues including gear grinding (especially 1st to 2nd and into 3rd gear when cold), high RPM lockout preventing shifts, notchy/difficult shifts, premature synchronizer wear, and in severe cases complete transmission failure. The transmission was originally designed for smaller four-cylinder vehicles and the synchronizers struggle to handle the Mustang's higher horsepower.
Common Symptoms
- Grinding noise when shifting into 2nd or 3rd gear
- Difficulty shifting when transmission is cold
- Notchy or stiff shifter feel
- Gear lockout at high RPM
- Popping out of gear
- Clutch chatter or judder
How to Fix
Ford has released multiple TSBs including TSB 11-3-18 recommending lower viscosity transmission fluid for cold shift issues. Replacing OEM fluid with Motorcraft XT-M5-QS or aftermarket fluid like Royal Purple Synchromax can help. Severe cases may require synchronizer replacement ($800-1,500) or full transmission rebuild/replacement ($2,500-4,500). Some owners opt for aftermarket transmissions like the Tremec Magnum ($4,000-6,000 installed).
Sources for this issue (1)
Nissan Altima · 2013–2023
The CVT transmission is known for reliability issues including shuddering, jerking, and complete failure. Nissan extended the CVT warranty on some model years to 10 years/120,000 miles due to widespread problems. High-mileage CVTs are particularly at risk.
Common Symptoms
- Shuddering during acceleration
- Jerky or hesitant response
- Delayed engagement from stop
- Whining noise from transmission
- Complete loss of power
- Check engine light
How to Fix
Change CVT fluid regularly with Nissan NS-3. Check if vehicle is covered by Nissan extended CVT warranty. If shuddering, may need valve body or complete CVT replacement. Avoid aggressive driving to prolong CVT life.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- OEM 2013-2018 Altima 2.5L CVT service kit
2013-2018 Nissan Altima 2.5L QR25DE CVT; select exact year. Maintenance/contamination service only, not a cure for internal CVT damage.
- OEM 2013-2018 Altima 3.5L CVT service kit
Service cannot repair confirmed mechanical judder or belt/pulley damage.
- OEM 2019-2023 Altima 2.5L CVT service kit
Confirm year, drivetrain and VIN.
- OEM 2019-2023 Altima 2.0T CVT service kit
2019-2023 Nissan Altima 2.0T KR20DDET CVT for this card; verify exact year/VIN. Not for the 2.5L engine.
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Owner tips & cautions
- TipChange CVT fluid regularly with Nissan NS-3.
- WarningThis is a high-severity issue - ignoring it can lead to costly repairs or safety concerns. Address it promptly.
- TipGet a proper diagnosis before replacing parts - similar symptoms can have different causes
Nissan Rogue · 2014–2020
Nissan Versa · 2012–2021
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P0730 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0730 mean?
P0730 stands for "Incorrect Gear Ratio." This code means the transmission computer detected that the actual gear ratio (calculated from input vs. output shaft speeds) does not match what it should be for the commanded gear. In other words, the transmission isn't delivering the correct gear, which often shows up as slipping, flaring RPM during shifts, or being stuck in the wrong gear. It can stem from internal mechanical wear, low or contaminated fluid, or faulty solenoids and sensors. The vehicle may shift harshly or enter limp mode.
What are the most common causes of P0730?
The most common causes of P0730 are: Low or contaminated transmission fluid, Worn clutches or bands (internal slipping), Faulty shift solenoids, Dirty or sticking valve body, Faulty input or output speed sensor, Internal hydraulic/line pressure problems, Torque converter problems, General high-mileage transmission wear. The specific cause varies by vehicle.
How much does it cost to fix P0730?
Repair costs for P0730 range from $5 to $20,000, depending on the vehicle and root cause.
Which vehicles are affected by P0730?
Au7o has documented P0730 across 145 vehicle models from 32 manufacturers: Acura, Alfa Romeo, Audi, BMW, Cadillac, Chevrolet, Chrysler, Dodge, Fiat, Ford, GMC, Genesis, Honda, Hyundai, Infiniti, Jaguar, Jeep, Kia, Land Rover, MINI, Mazda, Mercedes-Benz, Mitsubishi, Nissan, Pontiac, Porsche, RAM, Renault, Subaru, Toyota, Volkswagen, Volvo.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.