2021 GMC Sierra 1500 Other or unknown Problems
- Complaints
- 44about this part
- Share
- 7%of 596 total for the year
- Median mileage
- —not reported
- Trend
- RisingComplaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.
NHTSA recorded 44 complaints about the other or unknown of the 2021 GMC Sierra 1500, 7% of the 596 complaints for this model year. 1 of these say a crash was involved and 1 a fire, according to the filers.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“Engine experiences missing when accelerating in lower speeds ...also now, and since driving for a few thousand miles, f umes are entering cabin frequently and causing nausea, 'headaches and burning of mouth, lips and eyes .....all the time. My youngest granddaughter got sick and so did my oldest son just this past weekend! As far as I know , police or dealership never inspected , nor did they acknowledge it! No warning lamps appeared”
NHTSA complaint #11668912, filed 2025-06“The plastic frame of the rear sliding window failed. This has allowed water to enter the cabin, which can cause mold and other health issues. This seems to be a common issue with these trucks. My truck has a certified preowned warranty and GMC said they would only cover part of it. They charged me $400 as a deductible, which there should be no deductible per certified preowned warranty. I feel like GMC needs to put out an official recall.”
NHTSA complaint #11676125, filed 2025-07“There is a water leak in the rear passenger compartment of my vehicle. Unsure where water is coming from. Continued leaking poses a risk to my safety as I may be exposed to black mold as well as anyone else who is riding in my vehicle. The problem hasn’t been addressed by the dealer yet but this is a known issue. At this point I have spoken with a representative from the service department at the dealership but cannot get an appointment for several weeks. …”
NHTSA complaint #11747007, filed 2026-06“I took my truck through a car wash and then parked at my parents house. While the vehicle was parked, the trunk latch kept releasing. The trunk popped open. I left it open but you could hear the latch continually releasing and the lights blinking. This went on for an hour and I was unable to drive home because my trunk kept unlatching! A recall was released for other Sierras but not mine. Please investigate my vin and others that may be affected.”
NHTSA complaint #11691862, filed 2025-10“When I am in park my engine shuts off the light goes from green to orange which indicates it’s still on electrically. I have to turn on/off my vehicle multiple times for it to turn off fully. It’s an intermittent problem.”
NHTSA complaint #11668047, filed 2025-06Related service bulletins
- 11038463Oct 5, 2026This document assists GM dealer technicians with diagnosing torque converter concerns to ensure torque converter replacement is necessary. The torque converter part number will…
- 11038139Oct 5, 2026This preliminary PI was created to advise techniians in the field that they will not be able to perform a GDS automated bleed with the scan tool dues to a issue with the software…
- 11037555Sep 26, 2026This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it.
- 11037550Sep 21, 2026This PI communicates the proper part numbers for transmission connectors and internal harness to prevent confusion when ordering
- 11037253Sep 4, 2026This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
- 11036713Aug 27, 2026This document assists GM dealer technicians with diagnosing torque converter concerns to ensure torque converter replacement is necessary. The torque converter part number will…
- 11036392Aug 20, 2026This Preliminary information communicates to dealer to perform a MEC reset for wireless projection issues
- 11036196Aug 7, 2026This Preliminary information communicates an issue where an aftermarket autostop device or rear taillights is causing a dead battery.
- 11035709Jul 31, 2026This document assists GM dealer technicians with diagnosing torque converter concerns to ensure torque converter replacement is necessary. The torque converter part number will…
- 11035350Jul 23, 2026This PI provides information to repair the door water deflector which is not sealed properly allows water into the door jam/sill area.
Other or unknown: other model years
| Year | Complaints | Share of year |
|---|---|---|
| 2026 | 11 | 7% |
| 2025 | 15 | 12% |
| 2024 | 34 | 9% |
| 2023 | 54 | 11% |
| 2022 | 76 | 13% |
| 2021 | 44 | 7% |
| 2020 | 46 | 10% |
| 2019 | 45 | 7% |
| 2018 | 25 | 8% |
| 2017 | 35 | 10% |
| 2016 | 35 | 10% |
| 2015 | 67 | 9% |
| 2014 | 92 | 12% |
| 2013 | 42 | 36% |
| 2012 | 37 | 35% |
| 2011 | 73 | 26% |
| 2010 | 46 | 27% |
| 2009 | 38 | 16% |
| 2008 | 42 | 11% |
| 2007 | 15 | 6% |
| 2006 | 3 | 2% |
| 2005 | 6 | 3% |
| 2004 | 1 | 0% |
| 2003 | 2 | 1% |
| 2002 | 4 | 2% |
| 2001 | 2 | 1% |
| 2000 | 2 | 1% |
| 1999 | 6 | 4% |
| 1997 | 1 | 1% |
Other parts of the 2021 GMC Sierra 1500
322 complaintsTransmission and drivetrain
144 complaintsElectrical system
76 complaintsEngine cooling
49 complaintsFuel system
42 complaintsSteering
34 complaintsBrakes
25 complaintsBody and structure
13 complaintsLatches, locks and linkages
10 complaintsSuspension
10 complaintsLane departure
8 complaintsVehicle speed control
7 complaints
← All problems reported for the 2021 GMC Sierra 1500
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology