Certain vehicles may have a condition that could cause the cylinder 2 glow plug to fail. If this failure occurs, the Malfunction Indicator Light (Check Engine Light) will illuminate and a diagnostic trouble code will set. This special coverage covers the condition described above for a period of 15 years or 150,000 miles (240,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership. For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or after May 11, 2026, are covered by this special coverage and must be submitted using the labor operation codes provided with this bulletin. Claims with repair
full bulletin at NHTSA ↗2021 Chevrolet Suburban engine problems
moderate Owners of the 2021 Chevrolet Suburban have filed 65 NHTSA complaints about the engine, typically surfacing around 99,000 miles at roughly $3,100 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Failure mileage
Complaints
65
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2021 Suburban (this page) | 65 |
| 2022 Suburban | 34 |
| 2023 Suburban | 53 |
| 2024 Suburban | 16 |
1crash
What stands out
Of the 8 model years of Chevrolet Suburban we track for engine problems, this one carries the most owner complaints on file — 65.
Engine accounts for 36% of every owner complaint on file for this vehicle — the dominant problem area across 10 categories tracked.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
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 special coverage covers if an engine failure occurs in the vehicle as a result of the condition described above for a period of 10 years or 150,000 miles (240,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership. For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or after May 23, 2025, are covered by this special coverage and must be submitted using the labor operation code
full bulletin at NHTSA ↗Under Field Actions N252494000, N252494001, the service procedure includes performing a PICO test on vehicle engines within the identified suspect VIN population. If the engine passes the PICO test, the engine oil will be changed from 0W20 to Mobil 1 Supercar 0W40 dexosR. From that point forward, the engine must use 0W40 dexosR oil products for all future oil change services.
full bulletin at NHTSA ↗Certain vehicles listed above, may have a condition that could cause the engine coolant control valve to fail an onboard vehicle diagnostic test. If this condition were to occur, the Malfunction Indicator Lamp (Check Engine Light) will illuminate, and a diagnostic trouble code will set. Additionally in some cases, the engine cooling fans may run after the engine is switched off. Dealers are to replace the engine coolant control valve as necessary. The repairs will be made at no charge to the customer.
full bulletin at NHTSA ↗This technical bulletin provides a procedure to replace the camshaft actuator magnet to correct customer concerns of engine related shudder.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
2021 Suburbans with 5.3L and 6.2L V8 engines are failing internally at unpredictable mileage between 6,600 and 200,000 miles. The most common issue is lifter collapse—intake or exhaust lifters fail suddenly, producing a loud ticking or knocking noise, engine shaking, and often loss of power. Lifter failure frequently damages the camshaft, pushrods, and valves downstream. Owners also report sudden complete loss of engine power on highways at 35–80 mph with no warning lights beforehand. Engine seizure, crankshaft failure, and excessive oil consumption (1–2 quarts between changes) are widespread complaints.
Many owners describe symptoms lasting months—burnt oil smell, rough idle, or gradual noise buildup—before catastrophic failure. Others experience complete breakdown without any prior indication. Metal shavings in oil indicate bearing or crankshaft damage. Full engine replacement costs $12,000–$14,500. Repairs immediately post-warranty are denied. GM recall 25V-274 covers 6.2L rod/crankshaft failures but excludes most 5.3L engines despite identical failure modes. Owners report dealerships initially misdiagnose misfires as spark plug or fuel issues, delaying accurate diagnosis. Some vehicles fail a second time within 13 months of initial lifter repair. Regular maintenance and oil changes have not prevented these failures.
Same Chevrolet Suburban engine reports on nearby years: 2022 · 2023 · 2024
Failure modes owners describe
Lifter Collapse / Failure
Intake or exhaust lifters collapse, bend, or fail internally, causing the valve train to malfunction. This often damages the camshaft, pushrods, and valves downstream, and produces loud ticking/knocking noise. Collapse can happen suddenly without warning.
When: Reported between 6,600 miles and 200,000 miles; multiple owners report failures recurring within 13 months of initial repair or immediately after warranty expiration.
Symptoms owners cite: Loud ticking or knocking noise from engine compartment; Engine shaking or vibration, especially at idle; Loss of power or reduced acceleration; Check engine light (may flash); Cylinder misfire; Vehicle stalling or shutdown
Codes mentioned: P0300 series (cylinder misfire), Check engine light (specific codes not always cited)
Repairs/costs cited: Lifter replacement on one or both banks; replacement of pushrods, camshaft, valves as needed. Some owners report $5,010–$14,000+ for full engine rebuild or replacement when damage is extensive. One owner paid $1,301.75 for BTR Gen V DOD/AFM conversion kit plus $9,434.29 total labor and parts.
Recalls/TSBs owners mention: GM issued Technical Service Bulletin PIP5776C; some repairs covered under factory warranty (3 yr/36k mi); owners report warranty denial citing mileage overages (e.g., 500 miles past 60k limit). GM recall 25V-274 addresses crankshaft/rod failures on 6.2L L87 engines; 5.3L L84 engines with lifter failures generally not included in recall, despite owner requests. One owner received 'letter of coverage' but VIN still denied.
Excessive Oil Consumption
Engine consumes oil rapidly, requiring multiple quarts between scheduled oil changes. Oil low warning light illuminates frequently. Owners report this can persist even after warranty service or oil consumption testing.
When: Reported as early as 2,000 miles after fresh oil change; some owners experience it throughout ownership (30k–200k+ miles).
Symptoms owners cite: Engine oil low light illuminates after 2,000–5,000 miles of driving; Burnt oil smell from engine bay; Need to add 1–2+ quarts between scheduled oil changes
Codes mentioned: Oil low warning (not a diagnostic code per se)
Repairs/costs cited: Owners report piston and ring replacement, valve train service. One owner had extensive work done ($9,434.29 total) including pistons and computer reprogramming to disable Fuel Economy Management system. Another had oil consumption testing performed but told to return for further investigation; no repair performed.
Recalls/TSBs owners mention: GM performed oil consumption tests covering multiple service visits; some repairs approved under warranty. Post-warranty repairs denied, with dealers stating owners must repeat oil consumption test and pay out-of-pocket. Owners cite investigation EA25007 for potential bearing failure risk.
Camshaft Damage (Secondary to Lifter Failure)
Camshaft breaks, cracks, or becomes damaged as a direct result of lifter collapse or internal engine failure. Metal debris (bearing material, camshaft fragments) contaminates engine oil.
When: Occurs concurrently with or immediately following lifter failure; reported across the mileage range (6,600–118,000+ miles).
Symptoms owners cite: Loud rattling or knocking noise; Engine shaking and vibration; Reduced or lost power; Metallic debris in engine oil (silver, gold/bronze particles consistent with bearing material)
Codes mentioned: P0300 series (misfire codes)
Repairs/costs cited: Requires camshaft replacement and often full engine rebuild or replacement. One owner paid $200.04 for GM camshaft plus $5,010 for head gasket R&R. Many owners report $12,000–$14,500 for full remanufactured engine replacement.
Recalls/TSBs owners mention: No specific recall for camshaft-only failures on 5.3L engines. Repairs covered under factory warranty if within limits (3 yr/36k mi); post-warranty repairs are owner responsibility.
Sudden Loss of Engine Power / Stalling
Engine loses all propulsion without warning while driving at highway or city speeds. Vehicle may stall, fail to restart, or restart but enter limp mode. Check engine light may illuminate during or after the incident.
When: Reported at 16k–104k+ miles; can occur without prior symptoms or after other engine issues (lifter failure, oil consumption).
Symptoms owners cite: Sudden loss of motive power at highway speed (35–80 mph); Check engine light illuminates (may flash); Engine stalls or will not restart; Loss of propulsion message on dashboard; Vehicle enters limp mode or reduced acceleration mode
Codes mentioned: Loss of propulsion message (vehicle-specific alert), Check engine light (codes not always reported)
Repairs/costs cited: Varies widely; some traced to stuck solenoid in valve train (valve body part #24065354 reported unavailable), others to crankshaft/rod failure or general engine seizure. Full engine replacement quoted at $14,000–$14,500 or full rebuild.
Recalls/TSBs owners mention: Some repairs covered under warranty; others denied if VIN not included in recall 25V-274. GM recall 25V-274 covers 6.2L L87 engines; many 5.3L owners report denial despite identical symptoms. One owner noted dealership recommended higher-weight oil after recall service, but failure still occurred.
Crankshaft and Rod Failure
Crankshaft or connecting rods bend, break, or fail internally, causing catastrophic engine damage. Metal shavings appear in oil. Engine may seize or lock up completely.
When: Reported at 65k, 80k, 92k, 104k, and 132k miles.
Symptoms owners cite: Loud banging or knocking sound from engine; Engine shaking or violent vibration; Check engine light; Loss of power or inability to restart; Metal shavings in engine oil; Engine locked up / will not turn over
Codes mentioned: P0300 (misfire related)
Repairs/costs cited: Requires full engine replacement. Quoted costs: $12,000–$14,500 for remanufactured engine (GM Part 19420610 cited). One owner paid $9,434.29 for full repair including rod bearing replacement, pistons, timing chain components, and computer reprogramming.
Recalls/TSBs owners mention: GM recall 25V-274 covers crankshaft and rod failures on 6.2L L87 engines; many 5.3L L84 owners report VIN not included in recall despite identical failure modes. Some repairs covered under factory warranty; post-warranty repairs denied.
Engine Bearing Failure
Engine bearings fail or wear prematurely, resulting in metal-to-metal contact and catastrophic internal damage. Metal debris contaminates oil.
When: Reported at 65k and 107k miles.
Symptoms owners cite: Loud knocking sound; Metal shavings in oil; Loss of power; Low oil pressure alarm code
Codes mentioned: Low oil pressure alarm code
Repairs/costs cited: Requires full engine replacement; one owner paid $12,000+ for complete engine replacement including crankshaft.
Recalls/TSBs owners mention: No specific recall for bearing failure on 5.3L engines. Repairs are owner responsibility if out of warranty.
Engine Misfire / Cylinder Compression Loss
One or more cylinders develop misfires due to internal damage, carbon buildup, or loss of compression. Often secondary to lifter, valve, or piston failure.
When: Reported across mileage range; one case at under 20k miles.
Symptoms owners cite: Check engine light (may flash); Engine shaking or vibration; Rough idle; Service traction control, ESC, or forward collision warnings may also illuminate; Loss of power or hard acceleration; Loud knocking or ticking noise
Codes mentioned: P0300 (random misfire), P0301–P0308 (specific cylinder misfire)
Repairs/costs cited: Spark plugs, coils, and wires replaced in some cases without fixing the underlying issue. Deeper diagnosis typically reveals lifter collapse, valve damage, or piston/compression loss requiring engine rebuild or replacement.
Recalls/TSBs owners mention: Initial dealership responses sometimes misdiagnose as bad fuel or simple spark plug/coil issue. TSB PIP5776C addresses lifter-related misfires.
Engine Seizure / Lock-Up
Engine completely locks up or seizes, preventing any restart. Often associated with internal mechanical failure, loss of lubrication, or catastrophic metal-to-metal contact.
When: Reported at 23,906 miles (very early failure) and after extended driving in some cases.
Symptoms owners cite: Engine will not turn over / cranks but will not start; Knocking sound upon attempted restart; Vehicle stalls and becomes immobile
Codes mentioned: No specific codes cited; engine simply will not turn
Repairs/costs cited: Requires full engine replacement; no repair attempted in some cases. Estimated cost $14,000–$14,500.
Recalls/TSBs owners mention: Manufacturer notified in some cases; no recall coverage if VIN not included in 25V-274.
Synthesized from 65 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 6 most recent
The car was driving at 60 MPH on a regular commute to work and the car was stalling and shaking and soon after the check engine light came on with multiple issues.
Vehicle experienced sudden engine malfunction including rough idle, hard misfire, and flashing check engine light. Vehicle was diagnosed with a collapsed lifter and internal engine failure. Metallic debris was found in the engine oil, including silver and gold/bronze particles consistent with bearing material. A Chevrolet dealer inspected the vehicle and determined that the engine requires…
My wife was driving the car witb our kids when the check engine light came on and it started struggling and smoking. We got it to autozone to be scanned. The scan showed that it was a misfire on cylinder 3. After a mechanic trying to troubleshoot the problem he found that there was no compression. We towed the vehicle to a Chevrolet dealership where the found that the lifters in 1 bank needs to…
Went into limp mode on 11/6/25, took to the dealership where they found metal shavings in the oil due to a “stuck solenoid ‘A’”. Originally said that I’d need a whole new transmission, decided to do the cheaper easier repair and just replaced the valve train (not my choice) got it back on 11/13/25. On 11/24/25 I was on a very busy highway, at a red light, hit the gas when the light changed and…
We have a defective engine that stopped working after 120 miles. We can drive the car because it can leave us on the road or catch fire, this is what the mechanic told us, GMC option is to buy another car.
Engine is shaking like a bearing is going out, I've seen multiple recalls on this engine but for some reason my 6.2 isnt apart of them.
Had engine trouble with your 2021 Chevrolet Suburban?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2021 Chevrolet Suburban?
It's a documented issue but not catastrophic. 65 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Across the 12 complaints that reported odometer mileage, most engine failures cluster between 36,126 and 109,069 miles, with the median around 99,000. A quarter of owners report trouble before 36,126; a quarter make it past 109,069. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2021/Chevrolet/Suburban.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.