2024 GMC SIERRA 2500 Service Brakes Problems

Premature brake pad wear on all Brakes. All break pads worn down and had to be replaced at or before 25,000 miles. No trailer pulling and only light driving. Dealer stated rotors needed to be turned as well due to extremely low brake life.

This vehicle exhibits the same failure described in NHTSA Recall N232426400 — spontaneous unlatching after rain due to water intrusion into the exterior tailgate release switch. I’m requesting a goodwill replacement under GM bulletin # N232426400 as the failure mechanism and part are identical. It has caused brake failure and nearly killed me because of battery drain while driving. All American Chevrolet of Midland Texas is refusing to solve the problem and says no recall is available.

While trailering a large RV the information center sent me two warnings. The first was trailer brakes disconnected the second was service trailer brakes. Took it to the dealer they were unable to replicate so they blew me off.

Problem #1: Trailer brakes failed while pulling 40' fifth wheel trailer. Was driving at about 50MPH on a 55MPH road and was approaching a stop light. I went to apply my truck and trailer brakes simultaneously and quickly found out I had "lost" my trailer brake. This happened another two times within the next 10 mile trip to my house. I immediately disconnected my trailer and took my truck to the shop. The GMC Dealer fixed this issue, however, it is both scary and extremely dangerous to the public when something like this happens on a brand new truck. Problem #2: Right around 30,000 miles I was driving (unloaded) down the road at about 35MPH when I felt a hard clunk in the transmission followed by grinding noises - immediately a notice flashed on the dash stating the truck went into reduced acceleration and the check engine light came on. I brought my truck to a local GMC Dealer to be serviced on June 19th and they advised me it was the Allison transmission valve body. The part has been on back-order and my truck is still at the dealership sitting in the back lot with at least 4 other 2024 HD models. I called GM twice to inquire about Safety Recall N242454440 (covering 2020-2022 GM Vehicles) and recommend that it get extended beyond 2022 since the problem with the transmission valve body has not been resolved yet. I have not heard anything back from them since that call back in June.

024 GMC Sierra 2500 Denali Ultimate, which has suffered: •Five catastrophic engine failures at highway speeds. •Total brake failure, leaving the truck unable to stop. •Severe electrical malfunctions, including flickering headlights at night. •Retaliatory actions from General Motors after I refused to waive my legal rights. I have documented proof, including GM’s own service records, emails, and a 7-minute recorded statement from GM’s highest-level technician, confirming that GM installed the wrong computer module (1500 series instead of the required 2500 series) in my truck. Additionally, I have evidence that GM executives instructed technicians to conduct diagnostics, take apart the engine, and reassemble it—but NOT repair the defect—after I refused to sign an affidavit waiving my rights. Due to these failures, I suffered a dislocated shoulder in one of the incidents, and my [XXX] daughter remains traumatized to this day. Given the immediate danger this defect poses to other GMC Sierra 2500 owners, I respectfully request that NHTSA open an investigation and consider issuing a recall before a tragedy occurs. 1. Engine Failures Since 3,000 Miles – GM’s Own Work Orders Confirm Issue Since purchasing my 2024 GMC Sierra 2500 Denali Ultimate, I have experienced five catastrophic engine failures, all occurring while traveling at highway speeds (70 mph): •The truck suddenly lost power, dropping from 70 mph to 5-10 mph within seconds. •This created an immediate risk of being rear-ended or losing control on the highway. •GM’s own service records confirm that my engine issues began at just 3,000 miles. •GM dealerships misdiagnosed the issue FOUR TIMES, returning my truck to me in an unsafe condition. •The real cause was only identified after the FIFTH failure, when a GM-certified head technician finally determined that GM had installed the wrong computer module (1500 series instead of 2500 series). This means that for months, GM knew my vehicle w INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA

Trailer brake controller will intermittently stop working. “Check trailer wiring” will show up randomly on the display and no trailer braking will be available. This has happened with 3 different trailers. The trailer wiring was gone over and the issue is with the truck. Trailer brakes work with other trucks and aftermarket trailer brake controllers. GMC and dealer were notified and no fix is available. Researching online there are several complaints about this. The trailer brake signal should default to being sent similar to all aftermarket trailer brake controllers. This would be much safer rather than not sending the brake signal at all. This HD truck is rated to tow trailers over 20,000lbs and without trailer brakes it causes an extremely dangerous situation. I was forced to pull over on the highway and purchase an aftermarket trailer brake controller to continue safe travel.

Transmission and transfer case leaking. Masters cylinder ( brake booster) leaking

I purchased a 2024 GMC 2500 HD truck to pull a 2021 8,000 lb gvw camping trailer that is equipped with electric trailer brakes. My trailer has functioned perfectly related to the trailer brakes with my previous vehicle (2011 Toyota Tundra). With the GMC 2500, at approximately 3000 miles on the vehicle, a “trailer brake disconnected or disabled” and “check trailer wiring” warning began popping up on my information center of the truck. The trailer braking system would not function, though all other functions of the lighting and camera systems to the trailer worked indicating that the wiring and grounding were not an issue with the trailer. The brake system would intermittently return to normal. And then this warning and disconnected condition (i.e. no functioning trailer brakes) would return. This occurred rapidly, and very frequently. GMC has acknowledged a problem with some vehicles with this problem by publishing a TSB that purports to correct this issue (23-NA-149) that recommends replacement of the trailer brake control module (part no. 212327200000019B). I had this repair performed while on a trip in South Dakota away from my home state in Arkansas and the truck and trailer functioned as normal for approximately 3000 miles of towing. However, the issue has returned and my local GMC dealer repair shop (Little Rock, AR) places the blame on the trailer and not the truck. Towing with this 2024 GMC 2500 HD is very unsafe to the occupants and any others on the road due to loss of braking while towing a heavy load or navigating steep grades with a trailer equipped as described. This problem is now all over GMC/Chevy truck forums and is not just me or my combination. This issue is gonna get people killed.

The contact owns a 2024 GMC Sierra 2500. The contact stated while driving at an undisclosed speed, the sun struck the solar panel used to charge the battery, and the surge from the battery entered the pigtail going through the truck, and disconnected the brake module, causing it to become disengaged from the vehicle. The contact took the vehicle to the camper and vehicle dealer who both stated there was no issue for concern. The vehicle was not repaired. The manufacturer of the camper and the vehicle were made aware of the issue. The vehicle failure mileage was 8,000.

Mileage: 8,000

The contact owns a 2024 GMC Sierra 2500. The contact stated while stopped at an intersection, the vehicle moved forward while the brake pedal was fully depressed. The contact also stated on a level surface, the vehicle accelerated about 4 MPH without the accelerator pedal being depressed. The failure occurred on several occasions. The vehicle was taken to the dealer where the failure was duplicated; however, the dealer stated that the vehicle operated as designed. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 100.

Mileage: 100

Towing an RV with solar panels. When the trailer battery becomes fully charged and has a higher charge than the vehicle battery, the trailer brake control module becomes disabled. When this occurs, you have no trailer brakes. Combined weight of truck and RV exceeds 20,000 pounds. Trying to stop with only truck brakes is dangerous, especially if you are on a decent. I not only believe this to be a safety issues, but somebody is going to get killed.

While towing our RV trailer the trailer brakes become disabled. This is a known problem to GM and they have a TSB (23-NA-113) "Information on Trailer Brake Disabled or DTC Stored" This is a know problem and GM solution seems to cast the blame on the trailer manufacture.

When attached to a trailer with solar panels, the truck will intermittently disconnect the trailer electronics which disables the trailer brakes and trailer lights. This is because the solar energy is back flowing to the truck via 7 pin connector and overloading the circuit. Having a truck disable the trailer brakes and lights intermittently is very dangerous. Earlier model years of this truck do not suffer this issue. GM is aware and has TSB but no solution has been found on the truck side without disabling the solar panels on the trailer.