2021 Chevrolet Suburban Problems

What owners report

Owners of this Suburban year mostly describe engine problems — lifter and pushrod failures, bent rods, and in some cases complete engine seizure — often while driving at speed, followed by fuel pump control module failures that shut the vehicle down. Automatic transmission complaints center on harsh shifting, limp mode, and valve body replacement, and many owners say they were told the part was on backorder or that their VIN was outside a related recall.

1. 1
   Engine

   Engine lifter and valve train failure

   Mentioned in 21 of 60 sampled complaints

   Owners describe a sudden knocking, ticking or rattling sound, then misfire, shaking, loss of power and the check engine light, sometimes in limp mode. Dealers commonly diagnose collapsed or bent lifters and pushrods, often on one bank at a time, and in several cases replaced the engine after internal damage. Some owners say the repair was redone after the same failure returned, and some report the work was covered by warranty or a special coverage letter while other VINs were told they were not covered. Reported from roughly 6,000 up to about 160,000 miles, with many clustered between 20,000 and 105,000 miles.

   Recall 25V2740001 related service bulletin

   What to check: Listen for ticking or knocking on a cold start and on a test drive, and ask for records of any lifter, pushrod or engine replacement. Check whether this VIN is included in the engine recall and whether a special coverage repair has already been done.

   2 excerpts from owner complaints in NHTSA records

   “Engine while driving completely seized up. Crank shaft, cam shaft and oil pump water pump replaced. Low oil pressure alarm code present then sudden loss of power. Piston blown. There are similar recalls to 2021 suburbans however, this specific model is not in the recall. I was told I need a completely new engine. The car died in the middle of traffic and police had to call an emergency tow truck.”

   NHTSA complaint #11691379, filed 2025-10

   “Our Chevy Suburban High Country suffered sudden engine failure resulting in the vehicle to shake and smoke while driving on a busy intersection. The dealership diagnosed internal engine mechanical failure at only 46,000 miles. I believe this is directly tied to the known GM 6.2 L87 engine issues.”

   NHTSA complaint #11765469, filed 2026-09
2. 2
   Fuel system

   Fuel pump control module failure / stalling

   • 22 complaints (11%)
   • median 62,000 mi at 4.2 yrs old (9 state mileage, few)
   • filed 2023–2026

   Complaints describe the engine losing power or cutting out with little or no warning at highway and in-town speeds, sometimes failing to restart and once leaving the transmission stuck in park. Several owners were told the fuel pump power control module had failed and needed replacement, and several said the part was on national backorder. A number of these owners say they found a related recall but were told their VIN was not included. Mostly reported between about 30,000 and 90,000 miles, at both low and highway speeds.

   Recall 21V7390004 related service bulletins

   What to check: Ask whether the fuel pump power control module has been replaced and whether the emissions recall or service campaign for this part has been completed on this VIN.

   2 excerpts from owner complaints in NHTSA records

   “My 2021 Chevrolet Suburban stalled while driving in late September 2025 and had to be towed to a dealership. The vehicle is subject to an active fuel pump power control module safety recall that has been in effect since 2021. The vehicle was brought in specifically for repair of this issue. The work was processed under warranty, and I was charged a deductible. After learning the repair was directly related to an active safety recall, I requested reimbursement of the deductible, as recall repairs should be completed at no cost. …”

   NHTSA complaint #11714437, filed 2026-01

   “What component or system failed or malfunctioned, and is it available for inspection upon request? Fuel pump How was your safety or the safety of others put at risk? Yes, vehicle stopped unexpectedly and and wasn’t accelerating Has the problem been reproduced or confirmed by a dealer or independent service center?no Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? …”

   NHTSA complaint #11669413, filed 2025-06
3. 3
   Transmission and drivetrain

   Transmission harsh shifting and valve body failure

   • 14 complaints (7%)
   • median 79,800 mi at 5.5 yrs old (2 state mileage, few)
   • filed 2022–2026

   Owners report jerking or hard shifts between gears, especially at low speed or when moving between reverse and drive, along with a reduction in power and a message telling them to drive with care. Dealers typically diagnosed a failed transmission control valve body; some owners describe repeat dealer visits where the problem could not be reproduced before a later failure, and others report the vehicle stuck in limp mode. Reported from about 35,000 through 120,000 miles, often after months of intermittent hard shifting.

   Recall 24V797000

   What to check: Drive the vehicle through several low-speed upshifts and downshifts and try reverse-to-drive changes; ask for service records showing whether a valve body has been replaced or a transmission relearn was performed.

   2 excerpts from owner complaints in NHTSA records

   “Has been in the dealer multiple times for very hard shifting issues. Jerks when shifting gears from stop or in lower speeds. They have tried everything and cannot figure it out. But the techs have felt it when driving as well. It has been doing it for a long time. And it’s a concern when driving, I do not feel safe.”

   NHTSA complaint #11630671, filed 2024-12

   “History of transmission shifting issues shortly after purchase (CPO from Dealership). Vehicle was taken to two separate dealerships, several times for this issue while still under the 100,000 mile CPO warranty. Dealerships claimed they could not replicate the issue, however problem continued. Now at 1198xx miles, the transmission failed while driving. was accelerating from stop and and the vehicle bucked, the rpms jumped, the service indicator illuminated, and when the vehicle stuck in limp mode. …”

   NHTSA complaint #11652215, filed 2025-04
4. 4
   Electrical system

   Infotainment screen and electrical glitches

   • 24 complaints (12%)
   • median 75,000 mi at 4.4 yrs old (5 state mileage, few)
   • filed 2021–2026

   Complaints describe the radio and center display going blank, the backup camera stopping, and doors, liftgate or power running boards operating on their own. One owner reported that the blank screen also meant safety-related over-the-air updates could not be received. Dealers were notified in these cases; some owners say no repair or assistance was provided. Usually reported between about 60,000 and 90,000 miles.

   4 related service bulletins

   What to check: Check that the touchscreen and backup camera work, that software updates have been applied, and that the running boards and power liftgate cycle normally.

   2 excerpts from owner complaints in NHTSA records

   “Drove up to a stoplight 4th car in a turn lane, came to complete stop. Some cars closed ranks a little further so i released my foot off the brake and moved up a few more feet and stopped again. The car then accelerated with brake fully depressed and wouldn't stop. I then put gear to neutral Tac was very high maybe 5000. Put car into park and then turned off the engine. Restarted car and continued on my way. Contacted Chevrolet and my dealership for a service diagnosis coming up July19,2021. …”

   NHTSA complaint #11424684, filed 2021-07

   “The contact owns a 2021 Chevrolet Suburban. The contact stated that while driving 45 MPH, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended, and the vehicle decelerated unintendedly. Additionally, the vehicle failed to exceed 42 MPH. Later in the day, the gear shifter was shifted to reverse; however, the vehicle failed to reverse as intended. The vehicle was taken to the dealer, where it was diagnosed with transmission valve body failure. …”

   NHTSA complaint #11718829, filed 2026-02, 35,000 miles
5. 5
   Brakes

   Brake pedal and ABS master cylinder issues

   • 10 complaints (5%)
   • median 29,000 mi at 3.3 yrs old (2 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2021–2025

   Owners describe the brake pedal going hard or seizing while driving, or the pedal traveling to the floor, with brake system warning messages and, in one case, a grinding sound afterward. In one complaint the dealer found an ABS master cylinder that needed replacement and parts were unavailable; another owner described the brakes overriding a sudden unintended acceleration event. Reported from a few hundred miles to about 43,000 miles.

   What to check: Test the pedal feel at a stop and during low-speed braking, and ask whether any brake warning messages have appeared or an ABS master cylinder has been replaced.

   2 excerpts from owner complaints in NHTSA records

   “In traffic, approx. 10-15 MPH car in front stopped short. I put foot on the brake pedal and pushed the brakes pedal to the floor. The car did apply the brakes equally as hard as I was Appling brakes at the pedal”

   NHTSA complaint #11484256, filed 2022-09

   “At approximately 43,000 miles driving down the highway and lost power braking followed with a number of dash messages and lights. Took to dealer to discover the ABS Master Cylinder is bad and needs replaced and parts are 2 weeks out to have repaired. It appears after reading online this looks to be a problem with numerous people leaving comments etc.”

   NHTSA complaint #11578722, filed 2024-03

Buying note. Have a pre-purchase inspection focus on the engine for valve train noise or prior lifter work, and on the fuel pump control module and transmission valve body, since those account for most of what owners describe. Ask for the full service history and confirm the status of any open recalls or special coverage for the VIN before buying.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.