2021 GMC Sierra 1500 · symptom sheet
Transmission shudders, slips or shifts hard
- 43owner reports
- 61,000median miles
- $4,000median quote
- 0involved a crash
Newest report Sep 24, 2026 · checked Oct 2, 2026
137 of the 573 complaints on this car are about the transmission and drivetrain. 43 of those describe transmission shudder.
Tick what matches of 43 reports
Transmission shudder on other Sierra 1500 years
Report counts are for each model year on its own, so a newer car has had less time to collect them. Model years with too few reports of it for a sheet: 2014, 2022, 2023, 2024, 2025, 2026.
What this problem usually is
This is the biggest drivetrain group on the site: a transmission that shudders, slips, hesitates or bangs into gear. It's the everyday version of transmission trouble, where the car still drives but doesn't drive right, and it has three narrower sheets of its own for jerking, hesitation and slipping.
What got replaced
Owners who name the part that was replaced mention the torque converter (8 reports) and the valve body (4 reports).
Recalls and investigations
2 recalls on the transmission and drivetrain cover the 2021 model year. A recall on the same system isn't always the same failure, so read the defect text.
The transmission control valve may fail and cause the rear wheels to lock up.
The transmission control valve may fail and cause the rear wheels to lock-up.
All 7 recalls on the 2021 GMC Sierra 1500, with the owner complaints on each recalled system
What owners paid
8 of the 43 reports quote a price. Each dot is one quote. The middle half runs $600 to $8,000.
When it happens
The middle half of failures fell between 38,875 and 89,000 miles, from the 17 reports that gave a mileage.
Is this a known problem?
The manufacturer has sent NHTSA 21 service bulletins or notices for the 2021 GMC Sierra 1500 that deal with this problem. Newest first.
Federal rules make a manufacturer send NHTSA a copy of any notice about a defect that goes to more than one dealer or owner. Most of these are service bulletins, the repair instructions manufacturers send to dealers. NHTSA generally leaves safety recall bulletins out of this file, and recalls are listed separately.
Certain vehicles listed above, may have a condition where the transmission control valve has worn, resulting in a gradual loss of pressure within the valve.
This service bulletin advises the technician to check if the transmission cooler lines are twisted to correct customer concerns of Harsh Shift, Shudder, Surge, Stall, Transmission Overheating and/or High Transmission Fluid Temperature.
This service bulletin helps diagnose/reduce possible CCND issues on Transfer Cases - Service 4WD on DIC, Intermittent Failures, Noise Concerns, Driveline/Steering Vibration/Shudder, Intermittent DTCs/MIL Illuminated, Engagement/Disengagement/Ratcheting ...
This service bulletin provides information on Transmission Adaptive Functions and Correcting Low Mileage Harsh Shifts, Slips, or Flares.
17 more on the 2021 GMC Sierra 1500 page.
What owners wrote
“Vehicle began to slip or shift hard when putting it in gear or coming to a stop. The next morning the vehicle would not move when put in drive or reverse.”
Filed Feb 23, 2026
“Torque Converter failure confirmed by dealer: was driving at high way speeds when I noticed a slipping sensation from the transmission upon any sort of acceleration. No warning lights were illuminated or any symptoms leading up to the failure. This could have potentially caused me to lose any form of acceleration that would enable me to get off of the highway or away from a situation requiring sudden acceleration.”
Filed Sep 18, 2025
“Reached the 100,000 mile mark and the truck started shuddering. Took it to the dealership and they tell me the torque converter is coming apart and I need a new transmission.”
Filed May 31, 2025
“front idler gear for the transmission pump failed at 39500 miles. was fixed under GMC warranty. but now after getting the truck back the transmission has extremely harsh down shifts. still waiting for GM to figure out what to do next..”
Filed May 30, 2025 · 39,500 miles
Should you keep driving it?
This page can't tell you that. 0 of 43 reports involved a crash. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.
File your own report with NHTSA. Complaint counts are how a problem gets an investigation. How reports land on this sheet.
Guide Paid for this repair before a recall covered it? How recall reimbursement works
Other problems on this car
- Engine failure, knocking or rod bearing 126 reports
- Check engine light or misfire 104 reports
- Engine stalls or loses power while driving 88 reports
- Engine overheats or leaks coolant 53 reports
- Infotainment, screen or backup camera fails 26 reports
- Engine rattles or ticks 26 reports