2021 GMC Sierra 1500 · symptom sheet
Engine failure, knocking or rod bearing
- 126owner reports
- 58,522median miles
- $9,746median quote
- 0involved a crash
Newest report Sep 22, 2026 · checked Oct 2, 2026
350 of the 573 complaints on this car are about the engine. 126 of those describe engine failure, which makes it the most reported problem on the 2021 Sierra 1500.
Narrower sheets: Engine knocking or ticking (39 reports) · Engine seized (25 reports)
Tick what matches of 126 reports
Engine failure 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, 2015, 2016, 2017, 2018.
What this problem usually is
These are the reports nobody wants to file. The engine started knocking or ticking, the oil light came on, and then it seized or had to be replaced. Some owners had the replacement covered under warranty or an extension, and plenty were told they'd pay. Several narrower sheets split this group into knocking, seized engines and rod bearing failure.
What got replaced
Owners who name the part that was replaced mention the engine (122 reports).
Recalls and investigations
One recall on the engine covers the 2021 model year. A recall on the same system isn't always the same failure, so read the defect text.
The connecting rod and/or crankshaft engine components may have manufacturing defects that can lead to engine damage and engine failure.
All 7 recalls on the 2021 GMC Sierra 1500, with the owner complaints on each recalled system
NHTSA investigations into the engine on the Sierra 1500
Loss of motive power due to engine failure post recall remedy. Open.
Loss of motive power due to engine failure post recall remedy. Closed aug 20, 2026.
Loss of motive power due to engine failure. Open.
Loss of motive power due to engine failure. Closed oct 23, 2025, led to recall 25V-274.
What owners paid
9 of the 126 reports quote a price. Each dot is one quote. The middle half runs $4,600 to $12,000.
When it happens
The middle half of failures fell between 20,000 and 88,000 miles, from the 57 reports that gave a mileage.
Is this a known problem?
The manufacturer has sent NHTSA 5 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 connecting rod and/or crankshaft engine components in these vehicles may have manufacturing defects that can lead to engine damage and engine failure.
This bulletin advises the tech to inspect deeper into what may be to main cause of an engine failure.
This bulletin advises the tech to inspect deeper into what may be the main cause of an engine failure.
This Preliminary information communicates the following issues and directs dealership to inspect the engine harness for shorting.
1 more on the 2021 GMC Sierra 1500 page.
What owners wrote
“Dealer keeps ignoring engine knock noise states its normal , mpg is down dramatically . Shift to park , vehicle only has 34k miles and dealer does not want to repair under warranty due to vehicle being a 2021 Battery keeps draining for no reason , new battery added still does the same thing”
Filed Jun 6, 2025 · 34,000 miles
“First engine blown 31,904 miles, Lifter failure. Replaced with re-manufactured engine. Second engine failure at 68,000 miles, Piston rod failure. Piston blew thru engine block and engine bay caught on fire.”
Filed Apr 29, 2025 · 31,904 miles
“I was driving 50mph when my check engine light started flashing. The engine had very little power and there was a new consistent engine knock. I took to GMC dealership and they informed me that half of the engine lifters failed and a pushrod was bent. There was no warning prior to the incident. I have had the vehicle serviced only at the dealership and have only used premium fuel. The truck has 88,000 miles.”
Filed Mar 12, 2025 · 88,000 miles
“I've now had 2 engines fail catastrophically, One at 19,191 miles and the second failure at 80,661. Both are the 6.2L engine. The first had crank bearings that were black. The second I was not informed of the cause but that it was seized leaving me stranded on the roadside.”
Filed Mar 9, 2025 · 19,191 miles
Should you keep driving it?
This page can't tell you that. 0 of 126 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
- Check engine light or misfire 104 reports
- Engine stalls or loses power while driving 88 reports
- Engine overheats or leaks coolant 53 reports
- Transmission shudders, slips or shifts hard 43 reports
- Infotainment, screen or backup camera fails 26 reports
- Engine rattles or ticks 26 reports