Is the 2021 Gmc SIERRA 1500 reliable?

The 2021 Gmc SIERRA 1500 has 693 complaints filed with NHTSA (1.5x the segment average). Our reliability verdict: below-average. Most common issue: ENGINE problems.

What are common problems with the 2021 Gmc SIERRA 1500?

Top problems: ENGINE (300 complaints, avg repair $500); TRANSMISSION (123 complaints, avg repair $500); ELECTRICAL (70 complaints, avg repair $500). Issues typically appear around 50K miles.

Are there any recalls on the 2021 Gmc SIERRA 1500?

Yes, there are 7 recall(s): SEAT BELTS, SEAT BELTS, TIRES, TIRES:TEMPORARY/EMERGENCY SPARE TIRE, POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE, ENGINE AND ENGINE COOLING:ENGINE:HARD PARTS INTERNAL/MECHANICAL, POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE. Contact any Gmc dealer to verify if recalls have been completed on your specific vehicle.

How much does it cost to insure a 2021 Gmc SIERRA 1500?

Estimated US average full-coverage insurance for the 2021 Gmc SIERRA 1500 is approximately $1,753/year (sedan-midsize class). Actual quotes vary heavily by state, driver age, driving record, and credit — see the interactive insurance estimator on this page for state-specific pricing.

2021 Gmc SIERRA 1500

Q: Is the 2021 Gmc SIERRA 1500 often stolen?

The Gmc SIERRA 1500 was the #16 most-stolen vehicle in the United States in 2025 with approximately 6,300 thefts (NICB Hot Wheels data). Theft risk tier: above-avg.

Problems, Recalls & Reliability Report

Below Average

Quick Summary

The 2021 Gmc SIERRA 1500 has 693 owner complaints filed with NHTSA — that's 1.5x the segment average of 472. The most common issue is engine problems (43% of all complaints), specifically: the vehicle was bought brand new and was only driven for a week. it was in motion on the freeway when the engine started to sound noisier than usual, like that of an older truck. it was hard to notice on higher speeds on the freeway, but upon slowing down on curves, it got more obvious that someth. There are 7 recalls issued for this model year. ⚠️ 11 fire reports filed.

11 fire reports 3 crash reports

693

Total Complaints

Recalls Issued

4/5

Safety Stars

1.5x

vs Segment Avg

Known Problems(top 5 of 8)

ENGINE

300 complaints

43%

• THE VEHICLE WAS BOUGHT BRAND NEW AND WAS ONLY DRIVEN FOR A WEEK. IT WAS IN MOTION ON THE FREEWAY WHEN THE ENGINE STARTED TO SOUND NOISIER THAN USUAL, LIKE THAT OF AN OLDER TRUCK. IT WAS HARD TO NOTICE ON HIGHER SPEEDS ON THE FREEWAY, BUT UPON SLOWING DOWN ON CURVES, IT GOT MORE OBVIOUS THAT SOMETH
• WHILE DRIVING DURING WINTER CONDITIONS WITH TEMPERATURE AT 3 DEGREES ON A RESIDENTIAL STREET WITH LIMITED TRAFFIC, THE DIESEL FUEL IN THE FUEL FILTER GELLED UP WHICH CAUSED THE VEHICLE TO DISPLAY REDUCE POWER MODE AND THEN IMMEDIATELY SHUT OFF AND WOULD NOT START. THE VEHICLE COASTED TO A STOP IN TH
• TL* THE CONTACT OWNS A 2021 GMC SIERRA 1500. THE CONTACT STATED THAT WHILE DRIVING AT 60 MPH, AN ABNORMAL NOISE APPEARED UNDER THE HOOD. WITHOUT WARNING AN EXPLOSION OCCURRED. THE CONTACT MANAGED TO VEER TO SHOULDER OF THE ROAD GET OUT THE VEHICLE TO CHECK AND SEE WHAT THE NOISE WAS. THE CONTACT NOT

Typical onset: 50K miles Est. repair: $500🔥 5 fire reports

“THE VEHICLE WAS BOUGHT BRAND NEW AND WAS ONLY DRIVEN FOR A WEEK. IT WAS IN MOTION ON THE FREEWAY WHEN THE ENGINE STARTED TO SOUND NOISIER THAN USUAL, LIKE THAT OF AN OLDER TRUCK. IT WAS HARD TO NOTICE ON HIGHER SPEEDS ON THE FREEWAY, BUT UPON SLOWING DOWN ON CURVES, IT GOT MORE OBVIOUS THAT SOMETH”

— NHTSA complaint filing

When Problems Appear on the 2021 Gmc SIERRA 1500

Based on 139 owner complaints that included an odometer reading. Median mileage at time of complaint: 46K miles. Most complaints cluster in the 0-30K miles range.

Overall complaint distribution by mileage

0-30K

30-60K

60-100K

100-150K

150-200K

200K+

ELECTRICAL

In line with typicalmedian 16K mi · 16 reports

0-30K

30-60K

60-100K

100-150K

150-200K

200K+

BODY/STRUCTURE

In line with typicalmedian 18K mi · 6 reports

0-30K

30-60K

60-100K

100-150K

150-200K

200K+

BRAKES

In line with typicalmedian 22K mi · 5 reports

0-30K

30-60K

60-100K

100-150K

150-200K

200K+

ENGINE

Later than typicalmedian 53K mi · 66 reports

0-30K

30-60K

60-100K

100-150K

150-200K

200K+

DOORS/LATCHES

Later than typicalmedian 57K mi · 9 reports

0-30K

30-60K

60-100K

100-150K

150-200K

200K+

TRANSMISSION

High-mileage issuemedian 68K mi · 21 reports

0-30K

30-60K

60-100K

100-150K

150-200K

200K+

Mileage figures are self-reported by owners in NHTSA complaint filings. Peak bucket = the mileage range with the most complaints for that component; it reflects when owners noticed and reported problems, not necessarily when the fault first occurred.

Recalls (7)

SEAT BELTS17/12/2020

General Motors, LLC (GM) is recalling certain 2019-2021 Chevrolet Silverado 1500 and GMC Sierra 1500, 2021 Chevrolet Suburban and Tahoe and GMC Yukon XL and 2020-2021 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 vehicles. The seat belt brackets may not be secured to the seat frame in the front-row center seating position.

Risk: If a seat-belt bracket is not secured, the seat belt may not properly restrain an occupant in the front-row center seat position, increasing the risk of injury in a crash.

Fix: GM will notify owners, and dealers will inspect left-side and right-side front-row center seat-belt bracket attachments and reassemble it correctly as necessary, free of charge. The recall began January 26, 2021. Owners may contact GMC customer service at 1-800-462-8782, Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202314670.

Above-average theft risk

#16 most stolen in 2025

The Gmc SIERRA 1500 was the #16 most-stolen vehicle in the United States in 2025, with approximately 6,300 thefts reported to law enforcement.

Notes: Full-size truck; parts demand

Source: NICB Hot Wheels 2025 report + HLDI theft loss studies. Model-year ranking; not all years of this model have identical risk.

Estimated Insurance Cost for 2021 Gmc SIERRA 1500

Estimate only, not a quote. Modeled from NAIC + HLDI averages for a hypothetical 35-year-old driver with clean record + full coverage. Your actual quote depends heavily on your age, driving history, credit, ZIP code, and insurer.

Your state (affects local premium average)

Full coverage / year

$1,753

Full coverage / month

$146

Liability only / year

$598

vs US avg

+5%

How this estimate is calculated

US base full-coverage premium$1674

× state (US)1.00x

× vehicle class (sedan-midsize)0.96x

× theft risk1.06x

× safety rating0.98x

× vehicle age1.05x

= Full coverage estimate$1753

Coverage assumed: 100/300/100 liability + comprehensive/collision, $500 deductibles. Data sources: NAIC 2024 + HLDI loss studies.

Maintenance & Warranty

Recommended Gmc SIERRA 1500 Service Intervals

Oil change

8K mi / 12 mo

Tire rotation

8K mi

Brake fluid

36 months

Transmission fluid

45K mi

Engine coolant

150K mi

Spark plugs

100K mi

Cabin air filter

23K mi

Engine air filter

45K mi

Differential (AWD/4WD)

45K mi

Uses GM Oil Life System. Full-size trucks may have shorter differential and transfer case intervals if used for towing.

"Severe service" conditions (heavy towing, extreme temps, city stop-and-go) typically halve these intervals. Always consult your vehicle's owner's manual for the authoritative schedule.

Gmc New-Vehicle Warranty Coverage

Bumper-to-bumper (basic)

3 yr / 36K mi

Powertrain

5 yr / 60K mi

Hybrid/EV battery

8 yr / 100K mi

Corrosion (rust perforation)

6 yr / 100K mi

Roadside assistance

5 yr / 60K mi

These are the terms for a new Gmc. If you're buying a used 2021 SIERRA 1500, remaining coverage is usually pro-rated from the vehicle's original in-service date. Not all coverage transfers between owners — check with a Gmc dealer for VIN-specific remaining warranty.

Estimated Repair Costs

ENGINE(~50K mi)

$500

TRANSMISSION(~50K mi)

$500

ELECTRICAL(~50K mi)

$500

OTHER(~50K mi)

$500

STEERING(~50K mi)

$500

Estimates based on average reported repair costs. Actual costs vary by location, shop, and severity.

🔍 Pre-Purchase Inspection Checklist

Based on 693 owner complaints for this specific year, here's what to check or ask about:

☐
ENGINE: THE VEHICLE WAS BOUGHT BRAND NEW AND WAS ONLY DRIVEN FOR A WEEK. IT WAS IN MOTION ON THE FREEWAY WHEN THE ENGINE STARTED TO SOUND NOISIER THAN USUAL, LIKE THAT OF AN OLDER TRUCK. IT WAS HARD TO NOTICE ON HIGHER SPEEDS ON THE FREEWAY, BUT UPON SLOWING DOWN ON CURVES, IT GOT MORE OBVIOUS THAT SOMETH
Typically appears around 50K miles. Repair cost ~$500
☐
TRANSMISSION: TRANSMISSION SHIFTS HARD WHEN SHIFTING UP AND WHEN DOWNSHIFTING. VEHICLE JERKS WHEN GOING SPEEDS <40 AFTER COMING OFF HIGHWAY AT HIGHWAY SPEEDS >70.
Typically appears around 50K miles. Repair cost ~$500
☐
ELECTRICAL: STARTED VEHICLE EVERYTHING WAS NORMAL SHIFTED VEHICLE INTO DRIVE PROCEEDED FORWARD. WHILE DRIVING VEHICLES STEERING SEIZED I WAS UNABLE TWO MOVE THE STEERING WHEEL. IT WAS ALSO VERY DIFFICULT TO STOP THE VEHICLE BRAKES WERE NOT WORKING PROPERLY. MESSAGES CAME UP ON TO DISPLAY READING SERVICE POWER S
Typically appears around 50K miles. Repair cost ~$500
☐
OTHER: The only way to get the heater to work on your feet is to turn off defrost, turn on only feet, turn on AC and sync both sides. I live in North Idaho and when you do this your windshield fogs up and freezes. I have taken this to the dealership and was state "Works as designed by GMC". To me this i
Typically appears around 50K miles. Repair cost ~$500
☐
RECALLS: Verify all 7 recalls have been completed — free at any Gmc dealer
☐
General: Get a pre-purchase inspection from an independent mechanic ($100-$200)