2014 GMC Sierra 1500: complete transmission failure

Filed May 7, 2026 · Transmission · IL

The contact owns a 2014 GMC Sierra 1500. The contact stated that while driving downhill, the vehicle failed to accelerate as intended while depressing the accelerator pedal. In addition, the vehicle felt as if it were in neutral. The tachometer gauge revved up independently. No warning lights were illuminated. The contact pulled to the side of the road. The contact opened the front hood and noticed that one of the transmission lines had failed. The vehicle was towed to the residence. The contact replaced the hose and filled up the transmission reservoir. The contact stated that the failure persisted. The vehicle was taken to a specialty transmission place and rebuilt the transmission. The vehicle was repaired. The contact stated that a few months later the failure persisted. The vehicle was towed to the specialty shop, and the transmission was replaced. The contact stated that a few months later, while driving at an undisclosed speed, an abnormal odor was emitting from the front end of the vehicle. The contact was able to pull to a rest area, and when the front hood was open, the contact noticed that one of the transmission lines had a leak and transmission oil was being sprayed all over. The contact was able to replace the transmission hose. The manufacturer was not made aware of the failure. The failure mileage was unknown.Â

Filed Jul 6, 2025 · Transmission · MS

Catastrophic transmission failure. Original transmission failed at 113,00 miles. I replaced it at the dealership with a factory rebuilt transmission and that transmission failed after only 40,000 miles. Now the vehicle is back in the dealership shop and they want me to replace the transmission a third time. This transmission is the 6L80 which is prone to fail, the torque converter fails and the transmission locks up I contacted General Motors and filed a complaint with them and they said they would not take any action or assist me with the repair.

Filed Jun 27, 2025 · Suspension, Transmission · IA

Within the first week of buying my 2014 GMC 1500 SIERRA, the transmission fluid was black in griddy. I have had it flushed, then filter changed and new fluid put in within 2 week time frame. A week later had to put a new transmission in it. It barely would drive. So a purchase at 2,999 then to a transmission 4,800 and new control arm with ball joint with new axels. They were busted. Another 2,000. Its sicking. Advice

Filed May 5, 2025 · Transmission · SC

Transmission shutter, not shifting correctly. Had to replace transmission

Filed Aug 5, 2023 · FL

I have only owned the vehicle for about 5 months now and well it just started seeming like the transmission is starting to slip while also making a noise and just struggling to find what gear to stay in. I have service the car per the gm manual and I don’t drive the car anywhere but to work and back and that’s it. So disappointing that in going to have to replaced the transmission so soon.

Filed Sep 10, 2020 · Transmission · 87,000 miles · NJ

Driving down the highway one day around 65mph the vehicle began to shudder violently, reducing my speed to less than 45mph all the way home (all the while still shuddering) I took it to a well known transmission shop "whitty transmissions" in oak ridge nj only to have them drop the pan and find the transmission flooded with metal chips costing me a $3900+ rebuild. My transmission failed at 87,000 miles

Filed Apr 7, 2020 · Transmission · 158,000 miles · PA

My truck has 158,000 miles and had to have a new transmission put in as it was having problems accelerating, grinding and sounding like I was going over rumble strips.