2021 GMC Sierra 2500 Fuel system Problems
- Complaints
- 2about this part
- Share
- 4%of 52 total for the year
- Median mileage
- —not reported
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 2 complaints about the fuel system of the 2021 GMC Sierra 2500, 4% of the 52 complaints for this model year.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“After finishing a long drive south, I shut the engine off and a yellow engine code popped on. I connected my computer to it and revealed a P129F code (fuel pump control module). I have noticed that other GMC models have been included in a recall concerning this problem. The 2021 GMC 2500 Denali should be also since it is the same problem. This needs to be covered by the manufacturer since it is a constant problem.”
NHTSA complaint #11753689, filed 2026-07“I am reporting repeated failures involving both the transmission and diesel emissions (DEF) system on my 2021 GMC Sierra 2500HD Denali equipped with the 6.6L Duramax diesel engine and Allison 10-speed automatic transmission. While under warranty, the truck required replacement of the aftertreatment fuel injector and later the Reductant Control Module due to DEF/emissions system failures. General Motors also completed recall-related transmission software updates on the vehicle. …”
NHTSA complaint #11746749, filed 2026-06Related service bulletins
- 11017173Mar 21, 2025This informational bulletin instructs the tech when fuel/fluid is needed to be tested and where it can be sent for analysis.
- 11011443Oct 15, 2024This Preliminary information communicates information on faulty replacement K111 Fuel Pump Driver Control Module.
- 11010874Oct 15, 2024This bulletin provides information on how to look for and test for DEF or water in the fuel system and what the specs should be.
- 11009462Sep 23, 2024This informational bulletin provides information on availability for a locking gas cap for trucks are operated in high amount of dirt or dust which can migrate to the filler cap…
Fuel system: other model years
| Year | Complaints | Share of year |
|---|---|---|
| 2026 | 1 | 8% |
| 2025 | 1 | 4% |
| 2024 | 9 | 8% |
| 2022 | 4 | 9% |
| 2021 | 2 | 4% |
| 2020 | 2 | 3% |
| 2019 | 6 | 19% |
| 2018 | 6 | 17% |
| 2017 | 3 | 8% |
| 2016 | 12 | 20% |
| 2015 | 12 | 13% |
| 2014 | 3 | 10% |
| 2013 | 9 | 20% |
| 2012 | 5 | 16% |
| 2011 | 3 | 5% |
| 2009 | 2 | 6% |
| 2008 | 4 | 6% |
| 2007 | 3 | 4% |
| 2006 | 2 | 3% |
| 2005 | 3 | 3% |
| 2004 | 8 | 6% |
| 2003 | 15 | 9% |
| 2002 | 12 | 9% |
| 2001 | 12 | 9% |
| 2000 | 2 | 4% |
| 1999 | 2 | 6% |
| 1998 | 2 | 13% |
| 1997 | 1 | 7% |
Other parts of the 2021 GMC Sierra 2500
13 complaintsExterior lighting
9 complaintsEngine
8 complaintsBrakes
7 complaintsElectrical system
6 complaintsBody and structure
5 complaintsLatches, locks and linkages
4 complaintsForward collision avoidance
3 complaintsOther or unknown
3 complaintsAir bags
2 complaintsBack-over prevention (rear camera)
1 complaintsLane departure
1 complaints
← All problems reported for the 2021 GMC Sierra 2500
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 30, 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