2021 GMC Sierra 3500 Fuel system Problems
- Complaints
- 2about this part
- Share
- 10%of 20 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 3500, 10% of the 20 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.
“•The diesel exhaust fluid heater is a faulty component in the system, there is a back order on the part with no ETA • My pickup only does 55MPH right now and soon to do 5MPH you cannot drive on a public road doing 5MPH •There is thousands of other people having the same exact problem! •The DEF light is illuminated on my dash along with the check engine light, when you diagnose the error code it comes up with “P20C1 Reductant Heater C Control Circuit/OPEN””
NHTSA complaint #11454519, filed 2022-02Related 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…
- 11009430Sep 19, 2024This technical bulletin provides a procedure to correct the condition of Malfunction Indicator Lamp Illuminated with DTCs P2463 P2459 P11FB P11D3.
Fuel system: other model years
| Year | Complaints | Share of year |
|---|---|---|
| 2026 | 1 | 20% |
| 2024 | 5 | 10% |
| 2023 | 2 | 7% |
| 2022 | 1 | 3% |
| 2021 | 2 | 10% |
| 2020 | 6 | 12% |
| 2019 | 1 | 8% |
| 2018 | 1 | 7% |
| 2016 | 3 | 16% |
| 2015 | 2 | 6% |
| 2014 | 2 | 29% |
| 2013 | 2 | 14% |
| 2012 | 3 | 33% |
| 2011 | 2 | 10% |
| 2008 | 3 | 12% |
| 2005 | 1 | 4% |
| 2004 | 4 | 17% |
| 2003 | 1 | 14% |
| 2002 | 6 | 30% |
| 2001 | 8 | 22% |
| 1999 | 1 | 5% |
| 1998 | 2 | 17% |
Other parts of the 2021 GMC Sierra 3500
7 complaintsBrakes
5 complaintsElectrical system
4 complaintsEngine
3 complaintsOther or unknown
3 complaintsBack-over prevention (rear camera)
1 complaintsBody and structure
1 complaintsTires
1 complaintsVisibility (wipers, defrost, mirrors)
1 complaints
← All problems reported for the 2021 GMC Sierra 3500
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