general problems of the 2015 GMC Sierra 1500 - part 2

I bought my 2015 GMC Sierra 1500 certified and since then it has had vibrations when driving and hard shifts. The dealer has looked it over many times and said it's normal. Last month they said they sent GMC the readings and I haven't heard back. They have lied to me before about other vehicles and I'm tired of dealing with them not fixing it.

While operation my 2015 GMC 1500 denali pickup at normal conditions my vehicle produced a engine light. I was three blocks from my office so I proceeded there immediately to have my vehicle scanned for codes. This is where I found out that cylinder #7 had an issue. This cylinder is part of the afm system. I had the vehicle towed to galles Chevrolet for diagnostic services and an estimate for repairs. Up receiving the results (which) I will attach. Bank 1 and possibly bank 2 lifters and springs have failed. Thus possibly cause damage to the cam shaft. While I am aware that my vehicle is out of powertrain warranty (5 years / 100,000 mile), my vehicle only has 52,000 miles on it and very very well taken care of at all times. I am also aware of a class action law suite that pertained to the same exact issue on gm products from 2004-2014. Also service bulletins were produced by gm pertaining to this issue. Now I have been out of service of my vehicle for 3 1/2 weeks not to mention a potential $7000 repair, that should have never been in the picture! poor quality control on products for potential profit gains have cost many many customers pain, anguish, and money.

Had two lifters collapse and fail. Replaced transmission twice due to torque converter failure.

Will not come out of 4 wheel drive from the auto select position . . Stuck in 4hi will not release. Service 4 wheel light on.

Violent and erratic shifting during acceleration and deceleration. . . A simultaneous pop and jerk happens. . . Also when accelerating and hitting passing gear the truck seems to stall out and then quickly engages to apply more power than expected. . . This can be dangerous for a driver attempting to merge onto highways/highways! the jerking occurs on a regular basis and at various speeds on various highways. . .

Coolant is leaking. Smoke comes from the front of the vehicle when it's cold out. Temperature is fluctuating.

Aa soon as the warranty expired on my truck it start having problems with the transmission 🥴.

The vehicle is stuck in 4wd hi even though the indicator is set to 2wd. When turning at low speedfs the vehicle applies the rear brakes. The brakes do not apply when driving straight, only when turning at low speeds. It is dangerous when attempting to make turns from stops or parking.

A few months ago I was accelerating from a stop light the truck suddenly and violently jumped forward it had felt as if I was struck from behind. However no one was there! I did take it to the dealer and they said they could not replicate the condition and no codes were stored. Yesterday this happend once again! I would have sworn some one hit me, the truck shook and jumped forward so hard it felt as if a buss hit me. Once again no one there! I am making this complaint because I see more people are having theses issues and gm calls them "normal" sorry but I have driven trucks for years and have never had one do this! this is a potential hazard because if at any time a car was in front of me I would have most likely hit the car! please fix this issue!.

Transmission went out in 5 years and would not work any more.

My 2015 GMC sierra has the 8 speed transmission which has been an issue since I have owned the vehicle. I bought the vehicle used in the fall of 2018 and the truck/tranny ran good for about 10 months. Then in late summer and early fall of 2019, the truck jerking hard shifts started to appear. In October of 2019 I brought my truck into my dealer to have them look at my tranny due to the really hard shifts from 1st to 2nd or 2nd to 3rd and vice versa 3rd to 2nd and 2nd to 1st. I had to pay a $80 diagnosis fee and they reprogrammed my tranny and the ecu to smooth out the shifts and not make the shifts so hard. In all the software reprogram did get rid of the hard shifts, but in return now my vehicle drove like it has a 6 speed transmission instead of an 8 speed. In June of 2020 I brought my truck back into my dealer to look at my tranny again! now my tranny felt like it was always "hunting" for a different gear. When driving on the interstate at 75 mph 1600 rpm, if there was a little bit of head wind or I started to drive up a hill, the tranny would downshift and rpm's jump up to 2200 rpm to make up for the difference in road grade, same as when driving in town up a hillat 35mph. A 8 speed transmission should not be doing that! at interstate speeds (75 mph) my passenger side seat will sit there and just wiggle and shake back and forth. I have changed out ball joints and struts with brand new ones thinking that was the problem and the seat still wiggles back and forth. When driving my vehicle it feels like I am driving with a 6 speed transmission than an 8 speed. I have read that this seems to be a common problem in these model year gm vehicles and I feel gm needs to finally address this issue once and for all and keep their gm customers satisfied. I didn't plan on buying a 3 year old used vehicle for it to have the issues it has had since I have owned it.

When putting the truck into gear with the foot firmly on the brakes the truck will slam into gear causing the truck to jump forwards or backwards.

Tcc shudder.

Brake pedal goes soft and can hit the floor on occasion. Mostly happens with in reverse. 40k miles. Also transmission shifts are erratic. Rpm can shoot up between shifts.

When I'm cruising highway speeds the truck get a violent vibration and makes the vehicle uncomfortable to drive.

Transmission shifted hard, delayed acceleration at times, shuddered and jerked. This was usually slowing down to turn around 30 or 40 mph as the truck was in motion. After only two years the entire transmission had to be rebuilt. The transmission was shifting poorly the moment I drove it off the lot even if it "adaptive learning" you could tell there was something wrong.

Loses power when trying to accelerate, presents a problem when trying to maneuver in traffic and semi stalls for . 2 seconds enough to cause a delay.

When accelerating truck will sag and or hesitate. When you slow down and try to speed up the truck will hesitate for 5 or more sec. Before speed back up gm said that this is due to zero torque to me this is a safety hazard.

Tl- the contact owns a 2015 GMC sierra. The contact stated upon getting a state inspection they failed due to master cylinder, vacuum pump, brake booster, and hose leak. The dealer was not contacted. The manufacturer was notified of the issue. The failure mileage was approximately 33,00. Kh.

Safety issue: known issue to gm but company refuses to acknowledge as a safety issue. A large number of GMC/Chevrolet pickups have vibration issue at highway speeds causing stress and unnatural wear on vehicle components which might fail causing a crash at highway speeds. Gm dealers unwilling to solve issue on majority of affected vehicles (2014-2015).

The same part number in the other models are for recall except this model.

My truck suffers from vibration problems, the same thing that 10,837 other posts from other people suffering the same problem are talking about on this forum. . Read more...

The GMC sierra has a terrible vibration from 70 - 80 mph. It has been in the shop 7 times over the last year, 9 new tires, and the vibration still continues. I have attempted to resolve the issue with gm but there has been no resolution. The truck feels unstable and like something is going to break on the highway which is a safety concern. This vehicle has issues and it needs addressed.

Delayed engagement in drive, transmission clunks, rpm flares and truck quits moving unexpectedly. Shudder at 3- 50 mph, vibrates steering wheel and leaves an uneasy feeling the truck is going to quit moving.

First of all the headlights are very dim and at night cannot see nothing. Dealer said it is what is . Very bad !! also my sierra on window sticker states comes with all terrain tires it does not have all terrain tires . They are 265/65/r18 goodyear wrangler sra . I worked for goodyear and those tires are all season !!! not all terrain as specified on window sticker !! I talked to dealer and called customer service at gm they never call back and they said those are the right tires. They are not according to my attorney who states the window sticker is totally incorrect and is fraudulent check your tires and window stickers and compare and look on goodyears website you will see. Also my transmission clunks and knocks and shifts incorrectly dealer states its normal I spend 40k on a new truck and all I have are problems and gm does nothing. It downshifts horrible what can I do???.

The contact owns a 2015 GMC Sierra 1500. While driving 60 mph, the vehicle began to decelerate and the engine warning light illuminated. The vehicle was towed to a dealer where it was diagnosed that a gear cylinder fractured. The vehicle was repaired, but was unable to be driven. The manufacturer was not notified of the failure. The failure mileage was approximately 4,000.

The contact owns a 2015 GMC Sierra 1500. The contact stated that while driving at various speeds, the transmission failed to operate as designed causing the vehicle to sputter and not properly accelerate. Also, the digital speedometer display would not display properly due to a faulty radio. Additionally, the driver’s side headlight failed to properly illuminate due to moisture build-up inside the headlight assembly. The vehicle was taken to the local dealer who was unable to duplicate the failure. There was no service performed on the vehicle. The manufacturer was not notified of the failure. The approximate failure mileage was 1,000.

I bought the vehicle new in 9/2015. I reported a vibration between 75-80mph to the nearby gm dealer (twice). The dealer kept the truck for a few days and stated they could not correct the problem. I took the truck back to the original dealer where I bought it, they did a road force balance on the tires and reported the problem fixed. I took the truck back to the original dealer at 13k miles, they kept the truck for a few days and reported the tires needed to be replaced. They replaced the tires and stated the vibration has been resolved. I drove the truck for another 3k miles and noticed that the vibration was starting up again. At 18k miles, I returned the truck to the original dealer and they are going to try and resolve the problem a 5th time.

Brought in my 2015 GMC 1500 sierra truck in for vibrations issues at high speed of 70-75 mph. After 4 attempts GMC corp refuses to admit that there is a safety issues in driving this vehicle at a normal rate. They continue to remove and replace the tires. I have never owned a vehicle before that such vibration is felt in the cabin of the truck, passenger seat, foot petal, etc. That is so uncomfortable, that my wife refuse to drive in the truck due to its safety. GMC will not acknowledge any of these complaints but will say everything is of specs. Like others this is the worse vehicle I have ever purchased. Found more complaints like this has been filed, but same result, GMC will do nothing.

Extreme lag/delay- harsh engagement when shifting from park to reverse. Its like you are backing into something? when cruising 28-32 mph and releasing accelerator(as if you were coasting into a turn) when slowing the vehicle seems to shift up and lunge entering the turn. Clunks and shifts hard when cruising normally when you have to release the gas pedal and slightly reaccelerate, causing the driver to hesitate. Vehicle shutters and hard accel 10x worse when towing a 7000 # trailer (truck is rated over 12,000 lbs. Towing).

Truck starts to vibrate at 60 mph and gets worse the faster you go.

Driving my new 2015 GMC $52,000 GMC sierra, I noticed a distinct slipping/hesitation/general roughness when accelerating from a dead stop. The truck seemed to either have a transmission or engine problem. Took it back to dealership for them to check, and they indicated that this was "normal" and it was just the "cylinder deactivation" feature performing as designed. I explained to them that cylinder deactivation only typically happens at highway speeds and especially not from a stand still. They stuck by their story and again stated this was normal. My son came to see me and drove my new truck. Of course the truck hesitated and slipped from a dead start. "what's wrong with your new truck dad?" he asked. I told him it was 'normal and he just rolled his eyes. This is not normal for every sierra that GMC makes with the 5. 3 engine and 6 speed transmission would do this. I have read on numerous message boards and websites where this is an issue and gm needs to fix the problem. Also, the headlights are extremely dim and are barely usable. As others have stated, I can only see maybe 20-30 feet in front of me and not very bright at that.

Headlights are very poor (when wet road or in town) cannot tell they burning. . . I have 20/20 vision. . . . . . On slow down does not down shift. . . . Cannot accelerate. . . . The starter hangs up on start as if does not fire or no fuel pump.

I had made a complaint to chapdelaine Buick- GMC that my brand new truck did not seem to go into four wheel drive. I was told to bring the truck to the dealership and they would check it for me. I was told by the service department that the truck worked just fine in four wheel drive. I then noticed that the truck seem to shift very rough and I called the service department and told them that something had to be wrong. The service department asked me to bring the truck back down to them the next day and they would take it for a test drive. While I was driving the truck to the dealership it shifted from drive into neutral. I coasted to a stop put the vehicle into park shut off and restarted the engine and then shifted back into drive and tried to drive again. This time the vehicle service engine light came on and the vehicle stayed in low gear and would not shift into a higher gear. The best speed I could make was 10 mph. I stopped the vehicle and restarted two more times. On the second try the vehicle did go into drive. I made it to the dealership and they took it for a test drive and upon their return gave me a loaner vehicle. They had to rebuild the transmission on my brand new truck which took about three days. Thankfully this event took place on a back road with little traffic. If it had happened on a busy road an accident might have occurred.