P0735 - Gear 5 Incorrect Ratio
The transmission control module (TCM) has detected that the actual gear ratio for 5th gear does not match the expected ratio. This indicates internal slippage or mechanical failure within the transmission, often due to worn clutches, valve body issues, or low fluid pressure. The code is set when the TCM compares input and output shaft speeds and finds a discrepancy exceeding a calibrated threshold.
01. Most Common Causes
- Low or contaminated transmission fluid
- Worn or burnt clutch packs in 5th gear
- Faulty shift solenoid or valve body
- Internal transmission mechanical failure
- Faulty transmission control module (TCM)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Harsh or delayed shifting
- Transmission slipping in 5th gear
- Reduced fuel economy
- Transmission overheating
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Check transmission fluid level and condition; top off or replace if necessary.
Step 3: Perform a transmission pressure test to verify hydraulic pressure.
Step 4: Inspect wiring and connectors to the transmission solenoids and sensors.
Step 5: If no external issues found, remove transmission for internal inspection of clutches and valve body.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, driving with P0735 can cause further transmission damage and lead to complete failure. Have it diagnosed and repaired immediately.
How much does it cost to fix?▼
Costs range from $150 to $400 for fluid change and solenoid replacement, but internal repairs can exceed $2,000.