2021 GMC Sierra 1500 suspension problems

Filed Oct 3, 2026 · Body, Steering · OH · crash

Vehicle Safety Hazard Summary: This complaint concerns an incomplete, non-compliant post-collision structural repair on a 2021 GMC Sierra 1500 (VIN: [XXX]). It has resulted in immediate vehicle tracking failure, dangerous steering drift, and a compromised cabin safety cage following a passenger-side side-impact collision. 1. Severe Suspension and Tracking Misalignment • Electronic Alignment Failure: The post-repair electronic wheel alignment documents a Rear Thrust Angle of 0.17°. General Motors OEM specifications require a maximum allowable thrust angle of 0.10° or less for this 4WD Crew Cab chassis. The system printed a critical warning: "One or more values are not within specification. Tire wear, handling and safety problems may result." • Physical Wheelbase Displacement: Physical cross-measurements confirm a 1.25-inch tracking variance between the rear wheel wells. This proves the solid rear axle has shifted along the leaf springs due to a sheared centering pin or a bent axle/spindle assembly. • Road Hazard Handling: The truck exhibits a severe right-hand steering drift. The driver must hold the steering wheel significantly off-center to prevent the vehicle from pulling off the road. This creates an immediate risk of control loss during highway driving, sudden avoidance maneuvers, or wet weather. 2. Compromised Cabin Structure and Latch Failure • Structural Binding: The facility performed an outer B-pillar sectioning repair. Upon delivery, the B-pillar door check bracket was left un-torqued. When this structural hardware is torqued to factory specifications, the passenger door binds severely against the cab shell and will not latch or close without being violently slammed. This mechanical binding confirms the underlying inner high-strength steel pillars remain deformed, compromising side-impact and rollover crashworthiness. The vehicle is mechanically out of safe operating specifications, and the repair facility refuses to perform further corrections INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION

Filed Sep 18, 2026 · Engine, Suspension · UT

Both of my upper ball joints wore out and one broke as I was driving down the road at 65 miles an hour pulling me into the on coming lane of traffic, there was no warning of this. I had both upper and lower ball joint replace. If there had been another vehicle coming in the on coming lane we would have had a head on collision. At an earlier date the motor in this same truck had a fallen lifter which cause my motor to loss power, I was able to take it to the local GM dealer and they fixed it, there was no warning this was happening either. I am worried I will have a catastrophic engine failure and GM will not cover this. I have looked up my

Filed Jul 24, 2026 · Brakes, Steering · GA

Vehicle: 2021 GMC Sierra SLT | VIN: [XXX] Dealership: Carl Black GMC Roswell, GA (11225 Alpharetta Hwy, 30076) | Invoice #[XXX] | Service Date: [XXX] Paragraph 1 – Suspension Hazard: Dealership diagnosed a worn left upper ball joint (popping sound on left turns) and installed Rough Country aftermarket upper control arms on my stock-height Sierra SLT. These arms are designed for lifted suspension and alter factory caster/camber geometry, placing extreme stress on ball joints. This can cause sudden ball joint separation, wheel collapse, and total loss of steering control at speed. The dealership admitted on the invoice they "could not find branding" on original parts and chose non-OEM lift components without my consent or any safety disclosure. Paragraph 2 – Brake Failure & No Safety Warning: The same service included a full front/rear brake job (pads + resurfaced rotors) using their certified technicians and parts. After pickup, the brakes failed to operate properly. When I returned, the service manager refused to correct their own workmanship and instead quoted $1,900 to repair the very brakes they just serviced. Most critically, at vehicle pickup they issued no written or verbal safety warning—no "do not drive" instruction—despite the brakes being knowingly compromised, endangering me and the public. Paragraph 3 – Requested Action: The service manager was unprofessional, condescending, and refused accountability. I request an immediate the federal safety agency investigation into Carl Black GMC's unauthorized use of lift-kit suspension parts on stock vehicles, failure to warranty their own brake service, and reckless omission of safety warnings at delivery. This dealership pattern poses an imminent public risk. Please escalate. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Apr 23, 2026 · Brakes, Suspension · 77,000 miles · TX

The contact owns a 2021 GMC Sierra 1500. The contact stated that while her son was driving 55 MPH and depressing the brake pedal, the vehicle failed to slow down as intended. The driver attempted to use the parking brake to slow the vehicle, but the vehicle failed to slow down. The message “Braking System Failure” was displayed. The driver pulled over to the side of the road, and the passenger’s side front wheel detached and started leaning to the right before the vehicle came to a stop. The driver exited to inspect the vehicle and became aware that the front passenger’s side wheel was lying on the ground. The vehicle was towed to an independent mechanic, but was not diagnosed. The vehicle was then towed to another dealer, where it was diagnosed, and it was determined that the passenger’s side upper and lower control arms, ball joints, rack and pinion, brake rotor and pads, hub, outer tie rod, brake line, speed wheel sensor, wheel and tire, and suspension parts needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 77,000.

Filed Mar 8, 2026 · Suspension, Transmission · CA

Transmission Shuttering which was confirmed from from GMC dealership , but refused to do any repairs after confirmation or diagnostic and test driving. Demanded a 220$ fee be paid before releasing my vehicle back. Also gave GMC Bulliten # 25-NA-148 which states the same issues I'm currently having.

Filed Feb 4, 2025 · Engine, Suspension · 38,000 miles · MI

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving at an undisclosed speed, there was an abnormal clunking sound coming from the rear suspension. The check engine warning light was illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the rear suspension. The vehicle was repaired, but the failure reoccurred 4,000 miles later. The contact stated that while reversing, the contact heard an abnormal clunking sound coming from the rear suspension. The contact also stated that there was also a strong antifreeze odor permeating the interior of the vehicle. The vehicle was taken back to the dealer, but not yet diagnosed. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 38,000.

Filed Dec 2, 2024 · Steering, Suspension · CA

Front upper control arm ball joint separated from socket.

Filed May 24, 2024 · Suspension · 37,470 miles · IN

The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 40 MPH, the front driver's side wheel separated and fell underneath the front end of the vehicle, causing the vehicle to veer towards oncoming traffic. The contact was able to pull to the side of the road, where the vehicle was awaiting to be towed. The contact related the failure to the federal safety agency Campaign Number: 21V718000 (Suspension); however, the VIN was not included. The dealer was notified of the failure. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was 37,470.

Filed Aug 18, 2022 · Driver assistance, Steering · TX

I took my truck to the dealership because of my issues and they said they had many trucks going in with the same issue but there was no fix to it. The issues Popping Noise Heard On Hard Turns and/or Going Over Speed Bumps, Creaking Noise While Turning Wheel Left and/or Right, Clicking Noise Heard On Slow Sharp Turns.Also when you go over a bump the truck makes a spring loud noise to the point that the whole truck bounces. shifter is also very hard when you try to change gears.

Filed Aug 26, 2021 · Suspension · TN

On 22 December 2020, I received a 2021 GMC Sierra 1500 SLT X31 Truck. The day that I drove it I notice that the Truck was riding as though it had a low Tire issue. It was riding bouncy. I had no low tire light. I checked the Tire Pressure and they all was over inflated. I brought the pressure back to range, but the Truck was riding the same over rough and bumpy roads that the rear end of the Vehicle was shifting from side too side when you hit a bumpy or on rough roads. it felt like the rear end was coming off the ground very frighten. I called GM they assigned a case number and I took the Truck to Three dealership with the same answer that all bolts were tighten to Spec. Ok I get that, but did not address the problem that the truck is doing. I am not comfortable driving this truck especially when you have no I deal when your terrain will change and the back end of y0our Vehicle moves from side to sider on you.