GMC Sierra 1500 spongy pedal problems

Filed Jul 19, 2026 · Brakes · CT

Truck did not stop when applying brakes. Message displayed brake system failure and the breaks were spongy. The truck was towed to the dealer and required the master cylinder, gasket, and reservoir to be replaced with 23,403 miles. This appears to be an ongoing issue with GMC Sierra trucks and needs further investigation as this potential could be catastrophic. Also, as this appears to be an ongoing issue, owners should not be responsible for the cost associated with any repairs and should require an immediate recall.

Filed Jul 14, 2026 · Electrical, Engine · IN

I am submitting supplemental evidence regarding my 2021 GMC Sierra (VIN [XXX]) for Recall Query RQ26001, Campaign 25V‑274. Despite multiple repair attempts, my vehicle remains unsafe and non-compliant with GM Service Bulletin N252494002. The recall remedy was performed deficiently. [XXX] Northeast Buick GMC installed a remanufactured short block instead of the required complete engine, reused the original seized-engine oil pan (which continues to leak), and failed to address critical electrical damage. Documentation proves they deleted Labor Operation 14BUZ (Engine Electrical) after their technician noted a blown mega fuse. A second dealer, Penske Chevrolet, subsequently deleted Labor Operation 77CVZ01 from my repair order, demonstrating a systemic pattern of ignoring recall-required repairs. Electrical damage has cascaded, resulting in a burnt fuse block and active faults P0615, P0617, P26E4, P26E6, U0623, and U0284. More critically, within 24 miles of my last service, the vehicle developed a new, severe safety failure: the "Service Brake Pad Monitor" system failed, accompanied by a red "Service System" dashboard alert and a noticeably spongy brake pedal. These brakes were recently serviced, yet this failure introduces a new risk of crash not present prior to the recall "remedy." GM Executive Resolution Case XXX has provided no resolution, reimbursement, or safety assurance, ignoring all deadlines since XXX. I possess extensive documentation, including service orders showing deleted labor operations and diagnostic logs. I request this update be integrated into the investigation of RQ26001, as the current remedy is demonstrably ineffective and has exacerbated safety hazards. The manufacturer’s refusal to remediate these issues, despite my compliance, leaves me with an unsafe vehicle and significant financial loss. I am prepared to provide all supporting records to substantiate this complaint. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed May 19, 2026 · Driver assistance, Electrical · IN

2021 GMC Sierra AT4, VIN [XXX] , the federal safety agency Campaign 25V‑274, GM Case XXX. Brake pad monitor failed at 128,923 miles -- 24 miles after leaving Penske Chevrolet (released at 128,899, RO XXX, 04/17/2026). Brakes became spongy immediately following service. Monitor disabled entirely to stop recurring red Service System alert. Root cause is a burnt fuse block ground fault confirmed in writing by two GM-authorized dealers. Ray Skillman (RO XXX, 06/05/2025) documented the fault then deleted Labor Operation 14BUZ ENGINE ELECTRICAL from the recall repair work order. Penske documented verbatim: "all of these other faults share this same ground circuit." The recall repair at Ray Skillman used a remanufactured short block instead of a complete engine per N252494002. The original seized-engine oil pan has never been replaced across three dealerships and 128,000 miles. GM's own Part 573 filing states this defect "increases the risk of a crash." I drove 300 miles on an interstate on 04/22/2026 with active brake warning and no loaner because GM Executive Resolution refused to authorize one. Three GM dealers have inspected this vehicle. GM Executive Resolution Team [XXX] ) has not returned calls or emails and has not confirmed in writing this vehicle is safe to operate. OnStar issued a Critical Alert for P0617 on 04/15/2026. Zero brake faults existed in the 13 months prior to the Penske visit. This is a direct continuation of unresolved electrical damage from a botched federal safety recall repair at 384 days and counting. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jan 12, 2026 · Brakes · ME

While traveling at low speeds in parking lots and in the operation of parking, my 2016 GMC Sierra 1500 gets a hard brake pedal that goes to the floor but I have no brakes. I almost hit a person in a local grocery store parking lot, at the bank driving up to the ATM, and I almost lost my truck over a bank because the brakes failed. This has happened multiple times at low speeds but it is getting more consistent recently. It has endangered myself and others. It is only a matter of time until damage occurs or someone gets hurt.

Filed May 23, 2025 · Brakes · IN

I am experiencing an issue with a hard brake pedal on my 2014 GMC Sierra 1500. This same issue was previously addressed through a recall and special coverage program by GM, which I had performed. However, the hard brake pedal condition has returned, significantly impairing stopping power at low speeds. This poses a serious safety risk, especially when towing or parking. I can no longer park my trailer safely. The vehicle is difficult to stop, and braking distance has increased substantially. This is a known issue with this model and year. It appears the prior recall may not have adequately resolved the root cause. I am requesting that the federal safety agency investigate whether additional action or recall extensions are warranted.

Filed Nov 18, 2024 · Brakes · WV

Intermittently with slow driving such as parking maneuvers or creeping slow traffic at stop lights the brake pedal becomes very soft and depresses much more than normal and the brake action is decreased. Sometimes with this soft pedal it sounds like ABS is engaging. Pumping pedal sometimes restores brake performance.

Filed Feb 20, 2024 · Brakes, Electrical · AL

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.

Filed Dec 2, 2023 · Brakes · UT

Braking system is malfunctioning while driving at slower speeds. It has malfunctioned while backing up and almost hit another vehicle. It also malfunctioned while coming to a stop light. Brake system is not working as it should and is feeling spongy upon braking. It feels like the brake pedal is all the way to the floor before it will eventually stop the truck. In researching this problem, there was a recall on the secondary brake system back in Feb of 2020. I bought the truck in June of 2020. I never got any information that there was a recall from the dealership I bought it from. I am unable to drive my truck due to this problem. I have not taken the truck to a GMC dealer as of yet but planning to.

Filed Nov 19, 2023 · Brakes · TX

Electrical short on brake booster performance error code c0021 while operating vehicle . Brake pedal became stiff and higher than where I had it . Vehicle making hissing noises and will no longer start due to this error. Safety concern this is not part of a recall list. I nearly crashed. I had to utilize emergency brake.

Filed Nov 16, 2023 · Brakes · MN

It takes quite the amount of force to stop the vehicle brake pedal started feeling spongy and seems like it doesn’t have enough pressure constantly I have no brake fluid leaks or air in my lines it all comes down to the brake booster it seems like and I know a few vehicles had this problem but mine says it wasn’t but I believe it has been affected.