Gear 5 Incorrect Ratio
What does P0735 mean?
The P0735 code means the vehicle's onboard diagnostic system has detected: Gear 5 Incorrect Ratio. This is a critical severity code.
Common Symptoms
- Check Engine Light illuminated
- Slipping in fifth gear
- RPM higher than normal at highway speeds
- Reduced fuel economy
- Transmission may drop to fourth gear
Probable Causes (Ranked by Likelihood)
- Worn fifth gear clutch pack Very High
- Faulty fifth gear shift solenoid High
- Valve body malfunction Moderate
- Low transmission fluid Moderate
Step-by-Step Diagnostic Procedure
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Monitor fifth gear ratio using input and output speed sensors
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Check fifth gear solenoid operation with scan tool
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Perform line pressure test
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Check transmission fluid level and condition
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Transmission rebuild likely needed for internal wear
Frequently Asked Questions
Can I drive with code P0735?
Drive short distances only. An incorrect gear ratio indicates the transmission is slipping or not engaging properly. Continued driving can cause catastrophic transmission failure.
Does P0735 mean I need a new transmission?
Not always, but often. If the cause is a worn clutch pack or band, a transmission rebuild or replacement is typically necessary. If a solenoid or valve body is the cause, repair may be less extensive.
How is gear ratio measured for P0735?
The TCM compares input shaft speed to output shaft speed. The calculated ratio should match the expected gear ratio. When the ratio deviates beyond a threshold, the code is set.