2023 GMC SIERRA 2500 — Problems, Recalls & Safety Data

Driving at approximately 30-35MPH merging in traffic, the transmission shuttered and went into reduced power mode. ECM reported a 747 code and valve body failure.

Summary of Issue On [XXX], my family and I departed Kansas City, Missouri, for a camping trip to Great Smoky Mountains National Park (Cades Cove), Tennessee, approximately 800 miles away. We were towing a 2020 Forest River Salem FSX/RTX travel trailer, estimated at approximately 6,000 pounds loaded, using a Reese weight distribution hitch with integrated sway control. This load was well below the rated towing capacity of the vehicle. On [XXX], while driving without the trailer attached, the vehicle displayed multiple warnings including “Reduced Engine Power” and a transmission system alert. I immediately pulled over, shut the vehicle off, and restarted it. The warnings persisted. I cautiously drove approximately five miles to Twin City GMC, where the vehicle was diagnosed with a failed transmission valve body. Dealer and Manufacturer Response The service manager at Twin City GMC informed me that the required valve body was on national backorder, with multiple vehicles ahead of mine, and that wait times had reached up to three months. To confirm, I contacted Molle Chevrolet (Blue Springs, MO) and Randy Curnow GMC (Kansas City, KS). Both dealerships independently confirmed that this was a known and recurring issue, and that extended backorders for the valve body were common. I was informed that GMC could provide a daily rental allowance, but the rental vehicle would not permit towing. With my family, three dogs, and travel trailer stranded 800 miles from home, this option was not viable. As a result, I was effectively forced to trade in my truck and purchase a replacement vehicle to safely return home. Manufacturer Awareness and Complaint History GMC has demonstrated awareness of this issue through service bulletins, widespread owner reports, and media documentation addressing transmission valve body failures and parts shortages. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2023 GMC Sierra 2500. The contact stated that while driving approximately 35 MPH, the vehicle went into LIMP Mode, and the message "Service Transmission" was displayed. The vehicle was taken to the dealer, where it was diagnosed that the transmission valve body rod had failed. The valve body rod was replaced. It was unknown whether the vehicle was repaired. The vehicle remained at the dealer. The manufacturer was not notified of the failure. The failure mileage was approximately 44,546.

Bought a 2023 gmc sierra 2500 duramax. Went into limp mode took it to dealership the transmission was bad so they replace transmission after 3 month of dealer having my truck . Got the truck back still having issues with transmission not shifting right and the rear tires locking up at highway speeds .

The transmission control mod is bad. This is a persistent problem and that's why it is on back order for up to a year. It is unethical to not issue a recall as customers have to continue to pay for the vehicle while not getting a replacement of equal capabilities. I bought a 3/4 ton truck to haul for work, not getting something that can do the same while a pay $1000+ a month is wrong. For the NHTSA not to get involved, issue some sort of recall, and allow GM to continue to take people's money while their vehicles depreciate is wrong. Is this so the government can get paid back from GM for the bailout 15 years ago?