2018 GMC SIERRA 1500 Service Brakes Problems

I noticed there was an issue regarding the break assist system in my vehicle a few months ago when I went to go for a drive. It is available to be inspected. The issue regarding safety revolves around the difficulty to break. The low amount of brake availability is dangerous in the case of a situation that if I needed to break quickly it is extremely difficult to. I have not had a certified individual confirm the issue at this time. It has not been inspected. The warning message "Break Assist" comes up every time I try to utilize the brakes. I know there are previous recalls, although when I have tried to see if my truck falls under those recalls it does not.

The contact owns a 2018 GMC Sierra 1500. The contact stated that the vehicle failed to shift into gear as needed. The vehicle was taken to the dealer, where the contact was informed that an unknown part was loose. The vehicle was repaired. Additionally, the contact stated that while driving at various speeds, there was an abnormally loud sound coming from underneath the vehicle near the transmission. The vehicle was taken to the dealer, where the contact was informed that no failure was found. The contact stated that while driving 55 MPH, the vehicle started to decelerate unintentionally. The contact stated that there was smoke coming from the brake pedal. The contact pulled over to the side of the road and allowed the vehicle to cool down however, the brakes locked up unexpectedly. The vehicle was driven to the dealer to be diagnosed. The dealer informed the contact that the braking system had failed and needed to be replaced. The vehicle was repaired; however, the failure persisted. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 72,000.

Mileage: 72,000

The brakes sometimes lock up after use, or don’t disengage ( on one side) and the truck swerves ( steering wheel turns to the right ) into the next lane. I have to over correct and you can hear the brakes squeal. I will have to get off the freeway or the road. I am on trying to track off a couple of times for 5 to 10 minutes Until it stops doing it. It does it on average once to Twice a day. Was told could be brake calipers hoses, speed sensors sending the wrong information to the ABS system. It is very dangerous to drive the truck on the freeway doing 75 miles an hour!

I purchased my Sierra in 2021 and 2 weeks after purchase I got a warning for service stabilitrk and another for trailer brake system. This is very very annoying and also has my abs light on. My next issue is a code u510 for active grille shutter assembly. Please fix these issues as they are very common and unsafe. Not to mention as much ad I paid for this truck.

Transmission started to shutter at 24000 miles. Dealer said couldn’t find anything. ABS and Stabilitrack light came on at about 40,000 miles off and on. Both these problems could result in a crash. On freeway or streets. The display information/ radio has a mind of its own. Connects to any phone number or start the on star call and etc. it takes your attention off the road and can result in a crash.

I kept getting a constant alert on my vehicle dash board that said "service trailer brake system" the beeping alert was quite literally constant and it covered up the digital speed odometer, every time I tried to acknowledge the alert it would just pop up and start beeping again. I searched online and quickly realized that this problem with the brake system has plagued GM vehicles for several years and I attempted to fix the issue myself by buying factory parts that other GM owners stated was the issue but it did not correct the issue. I ended up needing to take it to a GM service center and my vehicle was there for 2 business days and it ran me several hundred dollars to have GM fix the issue in the electrical brake system. Again according from online research this problem has plagued a large number of GM vehicles and it would be nice to see GM issue a recall and correct the issue so other people don't end up in the situation I was in.

The truck is throwing a repeat of service trailer break

Getting message on console "Service - Trailer Brake System". This could result in trailer brakes to fail while pulling loads.

Have experience increased brake pedal effort, hard brake pedal, and/or potentially increased. stopping distance. The condition is more prevalent at low speed when softly applying the brakes. The Driver’s Information Center, (DIC) “Service brake assist” alert will activate. Extreme safety risk to myself and my children. Bulletin N182202780 & NT192268490 needs to be tied to this specific VIN Number as well.

Break system is making scratching noises as if it is a caliber breaking problem or a caliber piston problem, it is also setting off the trailer breaking system light on the dash as well as the trail traction control light.

Braking vehicle will cause brake pedal to vibrate and become soft while pressing it and requires more effort to stop vehicle. Service brake assist light laminates on info system. I know there is a recall for this currently but my vehicle is not listed for this all though i have the same issues. Recall is N202300860.

I purchased my 2018 GMC Sierra 1500 pickup truck new in 2018. To date it only has 28K miles on it. I have never used the trailer breaking system that it came equipped with. On 12/24/22 we were traveling to a family function for Christmas. The "service trailer break system" warning message came on and the chime chimed continuously until I got to my destination, about an hour away. This chime was very distracting and there was no way to turn it off. After arriving at my destination I turned the truck off hoping it was just a fluke. When I started the truck back up the "service trailer break system" warning light and chime continued. It continued for an hour on my way home. Again, this was very distracting and I was unable to focus 100% of my attention on the road and my driving. Thank fully I made it home okay. On 12/27/22 I took the truck to my mechanic to have him take a look. He said he has heard of this issue with these pickups. His diagnostic confirmed that the trailer breaking switch (on the dash) was functioning properly but said that the chassis control module was likely the culprit. He replaced the control module and it had to be programed by a factory technician. After this part was replaced the warning light or chime does not come on anymore. I have the defective part for inspection and the bill totaling $1191.86 for the repair upon request.

I purchased this 2018 GMC pickup in May 2021. Starting in Nov 2022 I started getting a sporadic SERVICE TRAILER BRAKE SYSTEM warning light and chime. I have never towed a trailer using this trailer brake system on the vehicle, but the warnings come on sporadically. I have done some research and found this is not an isolated case as others have reported the same problem. Some owners have replaced the dashboard controller at their own expense, however this is now a well documented problem that goes beyond an isolated case. This is a defect of the trailer brake controller and should be recalled by GM at GM expense. It is a hazard to driving when the visual and audible chime come on sporadically. It's a distraction to safe driving and requires immediate intervention. I did advise my local dealer of the problem when the vehicle was serviced Dec 2022, however they did not have a technician available to work the problem. So I continue receiving the visual and audible warning every time I drive the vehicle. Please highlight this problem within your organization for a possible safety recall.

Breaks are not working

While driving 35 miles per hour in the early morning hours I came to a 4-way intersection and applied the brakes slowly. Suddenly, I lost all power in the brakes and the steering wheel locked up. The lights, and stereo remained on, and my dash board display immediately showed a red check engine light. I immediately turn on my hazard lights, turned the ignition key off and tried to restart the truck. There was no clicking sounds. The truck would not start but the lights dimmed and the dash display now showed an intermittent yellow, flickering check engine light. After roughly 30 minutes while waiting for AAA to arrive I tried the ignition key and the truck started up with a red check engine light. Rather than attempting to drive I had AAA tow my vehicle to the Chevrolet dealership where I purchased the truck.

Received an error on the dash saying "Service Brake Assist". At the same time the brake pedal became very stiff and braking power was decreased significantly. I have received this same message and brake pedal stiffness with reduced braking power three times in the last 4 days.

The service alert for the trailer brakes keeps going off constantly and continues to go off persistently almost making the vehicle undriveable. I was informed to file a complaint with your company by my local dealership as this is a recurring issue with GMC trucks.

*A message and alarm kept going off on our truck "Service Trailer Brake". We are not towing a trailer, nor had we had a trailer hooked to this vehicle since 2019. It began only going off occasionally, but within a few weeks it was going off constantly. It would show repeatedly on the dash and the alarm would sound over and over. Trying to turn off the system was not successful, no matter how many times we hit dismiss. It was totally distracting and worrisome that something was wrong with our braking system in general. *The constant alarm and dash display made driving a very distracted experience. It is so loud that you cannot hear other outside noises. We were also concerned about the safety of our regular braking system. *I called the dealer where our truck is regularly serviced. They immediately said "Is it the Trailer Assist Alarm?," so it was obvious that this is happening to other owners regularly. It took several days to get in for an appointment. The shop mgr helped us to locate and pull the alarm fuse to stop the noise, so we could drive it to the dealership later in the week. The display was still going off when I pulled the truck into the dealership, as it has done all the way there (17miles from my home). *It was inspected by the GM dealership (Schwarz, INC. Honesdale, PA) and the defective switch was replaced at a cost to us of $127.14 on 08/11/2022. *This issue started several months ago (Feb 2022?), but it was a one time thing. So, we thought it was just a fluke. Then, a month or so ago it started again, but was happening only once or twice and would then disappear for days. Then, 2 weeks ago it began to happen continuously.

I am getting a service alert for the Trailer Brake System. It is constant and loud and distracting and a significant safety hazard, not only because of the distraction, but also because it renders trailer brakes completely useless

I was stopped at a fast food drive thru and then I tried to go to the next window and the truck wouldn’t move at all it will just rev so I put it in parked turned off the truck and turn it back on put it on drive and was able to move for like 40 ft then it did it again so I had it towed to my home

Trailer brake modulator on 2018 GMC Sierra does not consistently signal trail brakes to work when needed on our 7,500 pound RV trailer. GMC dealer eventually found that the battery cables were undersized as installed with the factory towing package on the 2018 GMC Sierra. The undersized battery cables do not consistently deliver adequate voltage to the trailer brake modulator on the GMC Sierra, so inconsistent electric brake function for our 7,500 pound RV trailer. Dealer had difficulty diagnosing the problem as being the wrong factory-installed battery cables to go with the factory-installed trailer towing package. So it cost us $1,600 to have the GMC dealer correct a problem caused by the GMC factory installing undersized battery cables. Fortunately, this did not result in a collision for us, but it might for someone else. Our 2018 GMC Sierra kept sending vague, randomly timed warnings to the dashboard to "Check Trailer Wiring." Very frightening, dangerous and costly (for us) mistake by GMC. Will the brakes work this time, or fail on the way home? Problem started in 2021 RV season, but took awhile for us to recognize the need to take to the GMC dealer for them to diagnose base cause. Took time for us to experiment changing trailer wiring connector on bumper and trailer brake control on the dash. Work for awhile, then fail. Work for awhile, then fail. Arrrrgh! Ask GMC to put more adequate battery cables on ALL their vehicles, please.

SERVICE TRAILER BRAKE SYSTEM - warning

“Service- trailer brake system” light keeps coming on. It is super repetitive. It comes on about every 30 seconds. It’s a loud beep that lasts quite a few seconds. Eventually, the beeping did not stop until the truck was stopped. Truck was just bought yesterday. Happens at any speed, even when stopped.

Yesterday afternoon I heard a beeping noise that was persistent and it said trailer brake check the same alert showed up today making it impossible to drive safely with the alert popping up every min

Im getting a service trailer brake system soon message on dash.

While driving parking lot speeds, when I pressed the brake pedal, it was very very difficult to push causing me to nearly rear end the car in front of me. This happened intermittently during a short time frame (5 minutes). While standing on the brake pedal hoping to stop in time, the brake pedal shook like the Antilock brakes were activating. This caused it to be even more difficult to stop in time. My vehicle is currently at my local dealership's service shop. When the issue occurred, a message stating "Service Brake Assist" popped up in my display.

At 50,000 miles the "service trailer brake system" error message appears constantly due to factory defects and its very common. These trucks should be recalled everyone is in danger on the roads and its a very common problem. I have not taken it to the dealer because i should not have to pay for this very common problem, it should be recalled.

The truck displayed warning lights for ABS, traction control, trailer brakes, and front park assist. Additionally speed control (cruise) did not function. This presented a safety issue. I took to dealer asap. They repaired by replacing left rear wheel speed sensor. Cost about $216. Appears to work correctly at this time.

THE FIRST THING THAT HAPPENED WAS THAT ALL OF THE ELECTRICAL SYSTEMS ON MY TRUCK WENT OUT AND MY TRUCK WOULD NOT START. IT FINALLY STARTED BUT IT WOULD NOT MOVE FINALLY IT WOULD MOVE BUT VERY SLOWLY THIS HAPPENED ON 11/20/2019 I HAVE DOCUMENTATION THROUGH ONSTAR FOR THIS INCIDENT. MY BRAKES STARTED SLIPPING ON 07/01/2020 AND STILL DO NOT WORK PROPERLY. MY TRANSMISSION HAS NEVER SHIFTED CORRECTLY. WHEN I ACCELERATE OR WHEN I SLOW DOWN THERE IS A SHUDDER AND A JERKING SOUND. AFTER SITTING FOR A WHILE WHEN MY TRUCK IS PUT IN REVERSE IT HESITATES AND THEN SEEMS TO JUMP INTO GEAR.

Mileage: 27,000

I RECEIVED A RECALL NOTICE FOR A BRAKE PROBLEM ON MY TRUCK. THE RECALL GAVE A LOCATION TO TAKE MY TRUCK FOR SERVICE. WHEN I CONTACTED THAT DEALERSHIP THEY SAID IT WAS A CANADIAN TRUCK AND THEY COULDN'T PERFORM THE RECALL REPAIR. SO I CALLED THE GM HOT LINE THEY SAID I HAD TO TAKE IT TO CANADA FOR THE REPAIR AND THAT WAS THE ONLY OPTION.

Mileage: 23,000

DEALER COMPLETED BRAKE SYSTEM RECALL ON 10-04-2019 N 192268490, NOW I READ ABOUT THE RECALL REPAIR MAY HAVE NOT FIXED PROBLEM, REQUEST ASSURANCE THAT PROBLEM IS FIXED.

Mileage: 20,305

TL* THE CONTACT OWNS A 2018 GMC SIERRA 1500. WHEN THE CONTACT SHIFTED INTO DRIVE, THE VEHICLE LUNGED FORWARD WITH THE BRAKE PEDAL DEPRESSED. AS A RESULT, THE VEHICLE CRASHED INTO A HANDICAP SIGN. THERE WERE NO INJURIES. PRIOR TO THE CRASH, THE VEHICLE WAS TAKEN TO BILL KAY CHEVROLET (LOCATED AT 601 OGDEN AVE, LISLE, IL 60532, (630) 968-2900) TO BE DIAGNOSED DUE TO HARD SHIFTING. THE CONTACT WAS INFORMED THAT A TRANSMISSION RE-LEARN OF THE SOFTWARE WAS NEEDED TO CORRECT THE HARD SHIFTING; HOWEVER, THE FAILURE BECAME MORE PRONOUNCED. THE CONTACT STATED THAT THE FAILURE WAS INTERMITTENT. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS INFORMED OF THE FAILURE AND DECLINED TO ASSIST. THE APPROXIMATE FAILURE MILEAGE WAS 13,000.

Mileage: 13,000

MY 2018 GMC SIERRA SLT'S BREAK PEDAL BECOMES EXTREMELY DIFFICULT TO PRESS, AND I CAN HEAR SOMETHING THAT SOUNDS LIKE AIR COMING FROM THE PEDAL. THIS HAPPENS ESPECIALLY AT LOWER SPEEDS.THIS CAUSED ME TO CRASH INTO A CONCRETE WALL AND DAMAGE MY TRUCK. MY TRUCK HAS ONLY 10,000 MILES.

Mileage: 10,000

DRIVING SLOWLY IN BUMPER TO BUMPER TRAFFIC. I WAS STOPPED WITH MY FOOT ON THE BRAKES, AND THE TRUCK STARTED MOVING FORWARD. I THOUGHT ENGINE SURGE, BUT IT WAS NOT. I PUMPED BRAKES HARD AND THE TRUCK STOPPED. THIS HAS HAPPENED 2 TIMES.

Mileage: 2,000

I WAS IN THE BANK ATM DRIVE THROUGH AND THE GUY AHEAD OF ME STARTED TO GO, I BARELY PUSHED THE GAS PEDAL AND HE DECIDED TO STOP. I HIT MY BRAKES AND THE TRUCK WAS HARD TO STOP, ALMOST LIKE THE GAS PEDAL RESPONSE WAS STILL IN THE GO MODE BEFORE IT HAD THE CHANCE TO REACT TO MY INPUT OF TAKING MY FOOT OFF THE GAS TO APPLY THE BRAKES. I CAN DUPLICATE THIS BEHAVIOR ALL THE TIME.

Mileage: 2,900

MY VEHICLE IS HACKED ANYTIME I AM DRIVING THE VEHICLE I AM NOT IN FULL CONTROL. THE VEHICLE STEERS ITSELF LEFT OR RIGHT WHILE DRIVING, THE BRAKES ARE ALWAYS ON WHILE DRIVING SOMETIMES BRAKING HARDER BUT ALWAYS ON. THE INFOTAINMENT SYSTEM HAS MANY GLITCHES. THIS VEHICLE HAS BEEN BACK TO THE DEALERSHIP MORE THAN 15 TIMES HAS BEEN OUT OF SERVICE OVER 35 DAYS GM EVEN FLEW A ENGINEER/TECH TO INSPECT THE VEHICLE AND SAYS THEY COULDNT FIND ANYTHING. THEREFORE THIS VEHICLE IS HACKED THERE ARE SO MANY ISSUES AND GLITCHES AND THE FACT THAT THE TRUCK ONLY ACTS LIKE THIS WHEN I AM DRIVING NO ONE ELSE. LIKE IT CAN BE TURNED ON AND OFF INSTANTLY. I HAVE TONS OF VIDEOS PICTURES AND SUPPORTING DOCUMENTS BACKING THIS. I NEED HELP THIS IS A SERIOUS ISSUE AND THERE IS SO MUCH MORE TO IT THAN I CAN TYPE HERE SOMEONE PLEASE GET AHOLD OF ME TO HELP OR POINT ME IN THE RIGHT DIRECTION. THIS VEHICLE WILL BE RETURNED TO GM SOON AS THEY ARE DOING A VEHICLE REPLACMENT PER ALL THE ISSUES BUT THIS NEEDS FURTHER ATTENTION BECAUSE IF THIS CAN HAPPEN TO ME IT CAN HAPPEN TO ANYONE . PLEASE HELP

Mileage: 200

LEFT REAR BRAKE LINE APPEARS TO BE INSTALLED IN HARMS WAY. THAT IS, AN OBJECT ON THE ROAD COULD BE STRUCK WHICH COULD TEAR AWAY THE BRAKE LINE RESULTING IN LOSS OF BRAKING POWER. OTHER VEHICLES OF THE SAME TYPE ON THE DEALER'S LOT WERE OBSERVED TO BE OF THE SAME DESIGN. IF THIS BRAKE LINE IS LOST DUE TO ROAD HAZARD, WILL BRAKING POWER BE LOST? PLEASE ADVISE. THANKS.

WHEN DRIVING VEHICLE AT ANY SPEED IT STEERS TO THE LEFT OR RIGHT . NOT A SIMPLE ALIGNMENT PULL OR WANDER I CAN FEEL THE WHEEL AS TO WHICH WAY IT WANTS TO STEER AT RANDOM. IF NOT PAYING ATTENTION OR IF YOU WERE TO LET GO OF THE STEERING WHEEL IT WILL GO OFF THE ROAD ABSOLUTLY NOT SAFE TO DRIVE. WHILE ACCELERATING THE VEHICLE FEELS LIKE THE BRAKES ARE BEING APPLIED AND DOES NOT ACCELERATE I HAVE TO GIVE EXCESSIVE GAS PETAL THROTTLE TO GET UP TO SPEED. THERE HAVE BEEN TIMES I HAVE CAME HOME FROM AS SHORT DRIVE AND I CAN SMELL THE BRAKES THEY SMELL BURNT HOT. ONE INSTANCE I WAS MERGING ONTO THE HIGHWAY AND THE TRUCK STRUGGLED TO GET UP TO 60MPH I HAD THE PETAL FLOORED AND THE TRUCK WOULD NOT GO OVER 65MPH THE ENGINE WAS @ 5000RPM MAXED OUT IT WOULD NOT SHIFT NOR GO FASTER THAN 65MPH. RANDOMLY TRANSMISSION THUNKS THUD AND SLAMS INTO GEARS WHEN THE AUTOMATIC TRANSMISSION IS SHIFTING AT LOW SPEED BELOW 50. WHILE DRIVING TRUCK FEELS LIKE THE DRIVE TRAN IS BOUND UP LIKE BRAKE IS APPLIED ON INDIVIDUAL WHEEL(S) . I HAVE HAD NOTHING BUT PROBLEMS WITH THIS TRUCK VERY WEIRD ISSUES THAT DON'T MAKE MECHANICAL SENSE. ALSO THE INSTRUMENT CLUSTER GAUGES AND INFOTAINMENT SCREEN DON'T LIGHT UP JUST BLACK SCREENS AFTER STARTING VEHICLE. HAPPENED 2 TIMES NOW. RADIO WAS OFF WHILE DRIVING THEN CAME ON FULL VOLUME WITHOUT TOUCHING ANYTHING. SERVICE STABILITY /STEERING WARNING CAME ON ONCE.I CAN HEAR FRONT TRANSFER CASE ENGAGE AND DISENGAGE AT LOW SPEEDS RANDOMLY WHEN IN 2WD. RANDOMLY STUCK IN LOW GEAR WHEN ACCELERATING FROM A STOP. AND YOU DON'T HAVE TO USE THE BRAKES MUCH TO STOP YOU BECAUSE AS SOON AS YOU LET OFF GAS PETAL THE VEHICLE NEARLY COMES TO A STOP WITHOUT APPLYING BRAKES. AND IF YOU ARE TURNING IT WILL AT TIMES COME TO A COMPLETE STOP. HAS BEEN TO DEALER 6 TIMES NOW THEY SAY EVERYTHING CHECKS OUT. THERE IS A MAJOR COMPUTER ISSUE OR IS HACKED PER ALL IVE RESEARCHED.

Mileage: 150