2018 GMC Sierra 1500: engine overheating

Filed Aug 11, 2026 · Engine, Steering · NC

Head gasket failure and overheating. After fixed, power steering has just failed during driving. Will have to have it towed to shop

Filed Feb 28, 2026 · Transmission · SD

I’ve gone through two transmissions on my 2018 gmc sierra 1500 both times the same issue. The gears are shot, hard shifting. Vehicle is well maintained. Both transmissions one original equipment and second bought at the dealership the truck was bought both only lasted over 80000 miles. Driving the truck loss of power or torque is noticed, then a hard shifting. Checked fluid all was good not seeing metallic shavings. Then the overheating of the transmission, faulty valve replaced with aftermarket bypass and did transmission flush. But each occasion there was an incident I would’ve driving on the interstate and vehicle would lose power and almost hard stop and cause a crash. Then vehicle would only go in reverse both times the transmission gave out. The only warning light that ever came on was a transmission overheating and nothing else. I’m currently in the process of having to get another transmission because of the same issue again. Vehicle was seen by a technician and deemed the transmission was shot again.

Filed Oct 30, 2024 · Transmission · 131,000 miles · OH

The contact owns a 2018 GMC Sierra 1500. The contact stated while driving 70 MPH, the vehicle started shaking violently, prompting the contact to pull over to the shoulder of the roadway. The vehicle returned to normal functionality, but upon the contact continuing to drive to his destination, the failure reoccurred. The contact stated that the RPM rapidly increased and the temperature gauge began to indicate that the engine was overheating. No warning lights were illuminated. The vehicle was taken to an independent mechanic, who diagnosed a failure with the auxiliary transmission oil cooler line, resulting in damages to the transmission. The contact was informed that the transmission needed to be replaced. The vehicle was not repaired. After investigating the failure, the contact related the failure to Special Coverage Adjustment: N182188930. The manufacturer was notified of the failure and referred the contact to the federal safety agency Hotline for assistance. The failure mileage was 131,000.

Filed Mar 5, 2021 · Engine · 42,000 miles · AL

Tl* the contact owns a 2018 gmc sierra 1500. The contact stated that a coolant smell would emit from the vehicle upon exit. The contact also stated that his vehicle had began to lose coolant at an abnormal rate and had to be frequently replaced. The contact took the vehicle to mcconnell automotive (3150 dauphin st, mobile, al 36606) where they confirmed that there was a crack in the radiator which resulted in a coolant leak. He was also informed that there was no recall on the VIN and that the warranty did not cover the repair. The manufacturer was notified of the failure and provided the same information as the dealer. The vehicle was not repaired. The failure mileage was approximately 42,000.

Filed Dec 14, 2020 · Engine · 47,000 miles · TX

Tl* the contact owns a 2018 gmc sierra 1500. The contact stated that while driving at various speeds, the temperature gauge indicated that the vehicle was overheated. No warning light was illuminated. The vehicle was taken to beck & masten buick gmc north (11300 fm 1960 west, houston, tx 77065, (877) 380-8433) where it was diagnosed and determined that the radiator was leaking coolant and that the radiator needed to be replaced. Coolant was refilled in the vehicle. The dealer contacted the manufacturer for assistance with repairs. The failure mileage was approximately 47,000.