While driving the truck it randomly shuts down, message on dash says shift to park to restart. No check engine light comes on or any other message. When it does this, the truck goes into park. It has been to the dealership 3 times and has not been fixed!
2026 GMC Sierra powertrain problems
severe Owners of the 2026 GMC Sierra have filed 19 NHTSA complaints about the powertrain at roughly $2,500 to repair (U.S. federal records, as of November 2026). Source: NHTSA Office of Defects Investigation. See powertrain across all vehicles →
Complaints
19
Recalls
0
Avg fix
$2,500
| Model year | powertrain complaints |
|---|---|
| 2022 Sierra | 109 |
| 2023 Sierra | 92 |
| 2024 Sierra | 71 |
| 2025 Sierra | 29 |
| 2026 Sierra (this page) | 19 |
1crash
When does it fail?
Of the 19 powertrain complaints filed for the 2026 GMC Sierra, here's the actual mileage breakdown — failures cluster heaviest at 0-25,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
Owners are still filing on this — the most recent NHTSA powertrain complaint for this vehicle was logged 23 days ago.
Powertrain accounts for 23% of all owner complaints filed against this vehicle, across 3 categories tracked.
What owners are reporting 6 most recent
On 10/15/2026 I was making a slow right-hand turn up a slight incline into a parking lot when the vehicle braked very hard and the transmission made a grinding noise. I looked at the dashboard, and it was showing that the truck shifted into park while I was driving. The electronic brake engaged as well. I tried putting the truck back into drive, but it would not go into drive. On the dash there…
5/08/2026: I stopped outside my garage. I then placed the truck in park and exited the vehicle while running. I went inside my garage and several minutes later, heard a crash. The truck had driven forward while unattended, and crashed into the corner of my garage, causing damage to both the building and the truck. Truck indicated it was still in park upon reentry. 5/11/2026 In a separate…
While driving on a public road, the 6.2L L87 V8 stalled without warning. There was heavy smoke and an oil trail of about 300 yards behind the truck. The engine would not restart, and the transmission would not shift into neutral. The truck was moved a short distance off the road and towed the next day to the selling GMC dealer. Odometer was 4,663 miles. Oil life remaining was 38 percent. The…
The powertrain/transmission is malfunctioning. The vehicle shutters, vibrates, and surges forward when coming to a stop, as if it wants to take off on its own. These symptoms began within the first couple of days after purchasing the vehicle on XXX. The valve body was replaced, but the issue continues. The vehicle is available for inspection. GM Case Number: XXX Dealership TAC Case: XXX This…
The contact owns a 2026 GMC Sierra 1500. The contact stated that while driving 5 MPH, the vehicle independently shifted into park(P). The check transmission warning light was briefly illuminated. The failure was a recurring failure. The dealer was contacted. The manufacturer was contacted by phone and made aware of the failure. The failure mileage was approximately 2,000.
Had powertrain trouble with your 2026 GMC Sierra?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the powertrain problem on the 2026 GMC Sierra?
It's a meaningful issue. 19 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $2,500.
At what mileage does the powertrain typically fail?
Based on the 19 complaints filed, powertrain issues most often appear around 2,633 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $2,500 for powertrain repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to powertrain?
No active recalls currently cover powertrain issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2026/GMC/Sierra.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.