OBD Codes

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

  1. 1Connect an OBD-II scanner and read all stored trouble codes and freeze frame data
  2. 2Check transmission fluid level and condition; top off or replace if needed
  3. 3Test the transmission speed sensors with a multimeter or scan tool
  4. 4Inspect wiring and connectors for the transmission harness
  5. 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

Frequently 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.