The contact owns a 2017 GMC Sierra 1500. The contact stated while driving 65 MPH and approaching a stop, the contact attempted to accelerate however, the vehicle failed to accelerate properly. There was no warning light illuminated. The vehicle was towed to an independent mechanic who diagnosed the vehicle and informed the contact that the transmission needed to be replaced. The vehicle was also taken to the dealer who confirmed that the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was 100,000.

- Salinas, CA, USA

Cold start after vehicle sits for a while vehicle shark bites and stutters. When you try and drive vehicle before it-€™s been warmed up significantly. It-€™s a safety concern because it feels very danger and could cause an accident. Alamo At caused my truck to stall out the other day with my children in it and a large accident. Dealership is dismissed my concern and says it-€™s normal gmc defects that I have to deal with. I will sue GMC if I have to.

- Mashpee, MA, USA

Transmission has been skipping since 35000 miles, it does it when driving more than 35 mph.

- Parker, CO, USA

Transmission experiencing hard shifts, especially at low speeds. Vehicle "jumps" forward with the hard shift. Took to dealer for service. Dealer indicated that GMC used the wrong transmission fluid during assembly of the vehicle. This was a known problem within GMC.

- Melrose, FL, USA

Truck has the 8 speed automatic transmission and at times makes a hard shift when pulling out from a stop. Truck currently shudders/shakes at around 1500 to 2000 rpm until the transmission goes into a lower gear. Feels like rumble strips in the road. Truck has only 32,000 miles on it.

- Bluefield, WV, USA

The contact owns a 2017 GMC Sierra 1500. The contact stated while driving 55 MPH, the vehicle began to shift hard, started shuddering, and lost electrical power. There was no warning light illuminated. The contact was able to push the vehicle to the side of the road with assistance. The contact was able to restart the vehicle however, the vehicle was shifting hard and was shuddering while driving. The vehicle was taken to the local dealer where it was diagnosed that the main power cord had failed and needed to be replaced. The vehicle was repaired; however, the failure persisted. The vehicle was taken to a second dealer; Fresno Buick GMC (5515 N Blackstone Ave, Fresno, CA 93710) where it was diagnosed that the transmission torque converter and the engine mounts needed to be replaced. Additionally, the dealer diagnosed that the coolant reservoir had failed. The vehicle was not repaired. The manufacturer was notified of the failure through email. The failure mileage was approximately 56,000.

- Coarsegold, CA, USA

I have carried my vehicle to the dealer 5 different time to report about the hard jerking when accelerating or backing up.First carried it on May 22 2018 and the last time i carried it in was March 2021it had 41083 miles i was told that it normal for the transmission to do that. I should have contacted you after i could not get any satisfaction from the dealership, i have 49800 miles on the truck and it is still doing the same thing. it jerk so hard sometimes it feel like the transmission id going to fall out.I have my paperwork for every time i carried it to the dealership.i just for tired of hearing the same thing I have brought 7 new GMC truck and have never had this problem. I have talk with several owner of 2017 trucks and they said they had the same problem. Will you please investigate. I carried my truck to FLOW of Fayetteville 910 860 9300 for the repair. Thank you.

- Fayetteville, NC, USA

When I'm coming to a stop and the vehicle starts downshifting, the last shift feels like the tranny is going to fall out. Forceful jerk and clunking noise. It's sporadic. One week it's almost every day, one week it seems fine. The dealership said they have heard this a lot and laughed when they told me the manufacturer has told them it's normal. It's definitely not normal.

- Anoka, MN, USA

. the engine mounted mechanical vacuum pump may decrease over time decreasing the amount of vacuum/ power brake assist, causing vehicle not to stop. Same as my 2016 GMC. I had to also have the ( evap control valve replaced). Transmission surges and on the down shift its knocking coming tyo a stop..in my rear ending a parked vehicle because of the brakes pulsating and not stoping scared me..dealership..dealership.no

- Bellville, TX, USA

Transmission shifts extremely hard in low speed. transmission temperature sensor is bad causing warning light to be on. Brakes fade at low speed causing abs system to growl.

- Williamstown, WV, USA

I'm having issues with my transmission/torque converter on my 2017 GMC Sierra SLT 6.2L which cause a heavy shutter and/or shake while driving. I have scheduled a follow up appointment for 11/22/21 after my vehicle was just in on 11/15/21. I currently have less than 57,000 miles on this vehicle. These issues create abnormal vibrations and shuttering under normal driving conditions which can adversely affect control of the vehicle. Furthermore, these issues affect acceleration and deceleration.

- Herrin, IL, USA

Within a couple of days after purchasing the vehicle new I noticed a vibration or shudder when the transmission shifted. Also, the truck would slam into gear almost like being hit in the back end, and on a few occasions while driving on the highway the truck would just downshift by itself thereby causing the engine RPM's to rev above 5,000. It has been to the dealer four times, transmission has been re-calibrated, the new and improved fluid flush and these problems still exist. The truck has just under 60K miles and has started downshifting on a regular basis causing the engine to rev. How long is that going to last before the engine blows or causes permanent damage?

- Spartanburg, SC, USA

GM has known issues, which I'm sure the NHTSA is aware of. This involves transmission in 2015-2019 model trucks, both GMC and Chevrolet, among other GM vehicles. In my research there have been no less than 13 TSB's issues by GM trying to rectify these issues. The latest TSB states that a new blend of transmission fluid is the fix. In my instance the transmission started shifting hard with less than 30K miles. Took to dealership and they reprogrammed the transmission control module. Fixed the issue for a while but then started back after about 10K miles. In Feb. 2020 with 60K miles a transmission temperature sensor failed on the transmission. I took it in to replace sensor and as a result they had to change the fluid at which time they told me they replaced it with the new recommended fluid. Now at 94K miles it has started producing the hard shuddering at certain speeds. This is the main problem the fluid change is supposed to fix. Well guess what. It does fix it. I'm now scheduled to take it back in on Monday 8-9-21 to have the torque converter replaced. The company I work for has about 12 of these model GMC trucks and 7 of them have had to go back in to fix this same issue. Some of them multiple times. I'm out of warranty and these repairs are not cheap. The biggest safety issue is the tranny could fail at any point going down the road and leave me with no drivetrain and potentially get hit. In my 40 years of driving and owning 20 vehicles between me, my wife and 3 kids I have never had a tranny fail. This is the first and GM has know about this issue for years. They need to be made to fix these issues and replace all transmission that are having issues and repay me the money I've already paid and the money I'll have to pay next week. This is ridiculous that NHTSA has not gotten involved enough to force GM to correct this. You need to force the hand of GM to make this right. You know of the problems, now get it fixed!!!!!!!!!!!!!!!!!!!!!!!!!

- Canton, MS, USA

Extreme hard shift from 1 to 2 regardless of power input. Also, sputtering after mantiaining speed (rpms jumping up and down, you can feel the power input increase or decrease). This also happens using cruise control. After researching, this is a major complaint on this vehicle.

- Yukon, OK, USA

The contact owns a 2017 GMC Sierra 1500. The contact stated while driving various speeds, the vehicle started to shudder. The contact stated no warning light was illuminated. The contact was able to drive to his destination. The vehicle was taken multiple times to luther family Buick GMC (3202 36th St S, fargo, nd 58104, (701) 639-4547) and 6 software updates were performed on the transmission. The contact stated that the failure persisted. The manufacturer was informed of the failure. The failure mileage was approximately 23,000.

- West Fargo, ND, USA

After coming to a complete stop at traffic stop light truck's transmission made a loud "clunk" sound. When attempting to accelerate on the green light truck, initially would not move then it lerched forward but would not shift out of first gear. Pulled off main road and into a parking lot where I shifted truck into park and turned off the engine. After waiting a couple of minutes I restarted the truck, shifted into drive and pulled back onto the street, but the truck still would not shift out of first gear.

- Eagle, ID, USA

The contact owns a 2017 GMC Sierra 1500. The contact stated that while accelerating at 85 mph, the vehicle independently decelerated to 70 mph without warning. The contact stated that the throttle no longer operated as needed. The contact had taken the vehicle to faulkner Buick GMC trevose (4427 E street rd, feasterville-trevose, pa 19053) on two occasions however, the mechanics were unable to diagnose the failure. The manufacturer was also notified of the failure and informed the contact that they had never heard of such a failure. The contact then spoke to an independent mechanic who informed him that the defect may be linked to a speed sensor and a computer malfunction. The contact then took the vehicle to another independent mechanic who reprogrammed the computer software. The vehicle was repaired. The failure mileage was approximately 19,906.

- Feasterville-Trevose, PA, USA

My transmission shifts very hard from 1st gear to 2and and then from 2and gear to 1st gear at which time I'm usually stopping and it seems to push the truck forward a bit. I've taken it to pekin il dealership and green Chevrolet in peoria il and neither one says there is anything wrong

- Canton, IL, USA

I was driving 50mph and was behind a semi as I started to pass him I noticed an oncoming car and decided there wasnt enough time to pass so I started to push the brake pedal to slow down and get back behind the semi and the brakes locked up which produced an uncontrollable spin in which I did a 180 degree spin and ended up going into the ditch backwards and tipped over on my side no airbags deployed either.

- Canton, IL, USA

I have an 8 speed transmission that stalls upon acceleration lurches and surges when trying to shift gears. When coming to a stop lunges forward due to a shift in the transmission. I have taken to the dealer multiple times and express my concerns they finally replaced torque converter and flushed transmission now they state that it is operating correctly.

- Omaha, NE, USA