P0730
Incorrect Gear Ratio
Severetransmission
Overview
The P0730 diagnostic trouble code signals a incorrect gear ratio condition detected by the transmission control module. This code relates to the automatic transmission system and may affect shift quality, timing, or overall transmission performance. Prompt attention is important to prevent further transmission damage.
Symptoms
- Check Engine Light (MIL) illuminated
- Harsh or delayed shifting
- Transmission slipping between gears
- Shuddering or vibration during acceleration
Common Causes
- Low or contaminated transmission fluid
- Faulty shift solenoid or solenoid pack
- Wiring issues in the transmission harness
- Worn or damaged internal transmission components
Diagnosis Steps
- 1Connect an OBD-II scanner and read all stored trouble codes and freeze frame data
- 2Check transmission fluid level and condition; top off or replace if needed
- 3Test the transmission speed sensors with a multimeter or scan tool
- 4Inspect wiring and connectors for the transmission harness
- 5Perform a transmission pressure test if accessible
Estimated Repair Cost
$300 — $2,500
Cost varies by vehicle, location, and repair shop. Includes parts and labor.
Commonly Affected Vehicles
Ford F-150Nissan RogueGMC SierraChevrolet Silverado
Related Codes
More Transmission Codes
P0218Transmission Over Temperature Condition
CriticalP0700Transmission Control System (MIL Request)
SevereP0701Transmission Control System Range/Performance
SevereP0702Transmission Control System Electrical
SevereP0703Torque Converter/Brake Switch "B" Circuit
ModerateP0704Clutch Switch Input Circuit Malfunction
ModerateFrequently Asked Questions
Driving with a transmission code is risky. Continued driving can cause further damage to the transmission, resulting in significantly higher repair costs. Have it inspected as soon as possible.