Engine-CodesGMC – P0734 GMC

P0734 GMC Code - Transmission 4th Gear Ratio Incorrect

Quick Answer

The P0734 diagnostic trouble code (DTC) for GMC vehicles refers to "Transmission 4th Gear Ratio Incorrect." This code indicates that there is an issue with the transmission's ability to shift into 4th gear properly. Common causes include Low transmission fluid level, Dirty or contaminated transmission fluid, Worn-out clutch components. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means
P0734 GMC indicates Transmission 4th Gear Ratio Incorrect.
Common causes
Common causes include Low transmission fluid level, Dirty or contaminated transmission fluid, Worn-out clutch components.
Severity
High - diagnose this code as soon as possible.
Can I drive?
Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Table of contents Created and updated by William Orellana on Sep 10, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0734 GMC Description

The P0734 diagnostic trouble code (DTC) for GMC vehicles refers to "Transmission 4th Gear Ratio Incorrect." This code indicates that there is an issue with the transmission's ability to shift into 4th gear properly. The transmission control module (TCM) monitors the gear ratios while the vehicle is in operation. If it detects that the transmission is not shifting into 4th gear as it should, it will trigger the P0734 code.

OBDII Code P0734 GMC - Transmission 4th Gear Ratio Incorrect
P0734 GMC Code - Transmission 4th Gear Ratio Incorrect

Common Causes of P0734 GMC

  1. Low transmission fluid level
  2. Dirty or contaminated transmission fluid
  3. Worn-out clutch components
  4. Faulty transmission solenoid
  5. Issues with the transmission control module

Symptoms of P0734 GMC

  1. Harsh or delayed shifting
  2. Reduced fuel efficiency
  3. Engine revving higher than normal before shifting
  4. Transmission slipping
  5. Illuminated check engine light

How to Fix P0734 GMC

  1. Check and top up transmission fluid levels
  2. Perform a transmission fluid flush and filter replacement
  3. Inspect and replace worn-out clutch components
  4. Test and replace faulty transmission solenoid
  5. Reset TCM and perform a transmission relearn procedure

Cost to Fix P0734 GMC

The typical repair costs for addressing a P0734 transmission 4th gear ratio incorrect code can vary depending on the specific cause of the issue. On average, repairing this problem can range from $200 to $1000, including parts and labor. However, it's important to note that diagnosis time and labor rates can vary based on location, vehicle make and model, and the extent of the repairs needed. It's recommended to consult with a trusted auto repair shop for a more accurate estimate based on your individual circumstances.

Tech Notes for P0734 GMC

Incorrect ratio Diagnostic Trouble Code (DTC) may indicate a component condition with piston seals, clutch plates, or solenoids or it may be caused by a faulty turbine or output speed sensor signal.

Need more information about the P0734 GMC code?

Need more information on how to fix the P0734 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0734 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0734 GMC Code

No Frequently Asked Questions about P0734 GMC Code found.

Discuss the causes and fixes for P0734 GMC OBDII Code

Code P0734 GMC comments

No comments found for this page.