P0729
Gear 6 Incorrect Ratio
When gear 6 is engaged, the measured ratio between the input- and output-shaft speed sensors does not match the expected ratio for that gear. This means the transmission is slipping in gear 6 rather than transmitting power solidly. Causes: worn clutch packs or bands, low fluid level or pressure, a stuck shift solenoid, or a valve-body fault affecting gear 6.
When gear 6 is engaged, the measured ratio between the input- and output-shaft speed sensors does not match the expected ratio for that gear. This means the transmission is slipping in gear 6 rather than transmitting power solidly. Causes: worn clutch packs or bands, low fluid level or pressure, a stuck shift solenoid, or a valve-body fault affecting gear 6.
Common causes
- high
Shift solenoid stuck
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-3300
- medium
Clutch pack worn or slipping
A plausible cause — test and verify before replacing parts.
Typical part cost: $220-3300
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
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Frequently asked questions
What does P0729 mean?
P0729 means "Gear 6 Incorrect Ratio". It is a generic OBD-II code that points to a fault in the transmission.
What are the most common causes of P0729?
shift solenoid stuck; clutch pack worn or slipping — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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