2021 Chevrolet Silverado 3500HD

What owners should know

Covers 2020–2026 · 6.6L Duramax L5P diesel and 6.6L V8 gas · Updated 2026-10-01

Researched from owner forums and NHTSA complaints and written by Know Your Truck. These are patterns in what owners report, not a guarantee about any particular truck.

Common failures & how to fix them

Parts and video buttons search for your 2021 Chevrolet Silverado 3500HD. Always confirm a part fits using your VIN. Brakes, steering, fuel and airbag work affects your safety, so if you're not sure, have a qualified mechanic do it.

• 10-speed transmission valve body failure

  Dealer (recall)

  Signs: Sudden hard downshifts, limp mode, or rear wheel lock-up on diesels.

  Fix: Covered by GM recalls on 2020–2022 diesels. Other repairs are usually under warranty on newer trucks. Ask a dealer for all open recalls and bulletins.

  May be covered free by recall 24V797000 / 26V083000. Check the VIN at nhtsa.gov/recalls.

• Trailer brake controller warnings

  Easy DIY

  Signs: 'Check trailer wiring' or 'Trailer brakes disconnected' messages that cut the trailer brakes.

  Fix: Clean and inspect the 7-pin trailer connector and the trailer's wiring first. If it continues, have a dealer check for bulletins and module updates.

  Shop: 7 pin trailer connector▶ How-to videos

• Power tailgate opens unexpectedly

  Dealer (recall)

  Signs: The tailgate unlatches by itself, often after water gets in.

  Fix: Covered by GM recalls on 2020–2024 trucks with power-unlatching tailgates.

  May be covered free by recall 24V060000 / 24V894000. Check the VIN at nhtsa.gov/recalls.

• Steering gear shaft can break (2024)

  Dealer (recall)

  Signs: Loose steering or a clunk. In rare cases loss of steering.

  Fix: Covered by a GM recall on some 2024 trucks.

  May be covered free by recall 23V549000. Check the VIN at nhtsa.gov/recalls.

Recalls

A recall doesn't mean a truck still has the problem. Enter the truck's VIN at nhtsa.gov/recalls or ask a dealer to see whether the repair was done.

• Power Train:Automatic Transmission:Control Module:Software

  Oct 2024 · #24V797000

  General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel engines. The transmission control valve may fail and cause the rear wheels to lock-up.

  Risk and fix

  Risk: Rear wheel lock-up can increase the risk of a crash.

  Fix: Dealers will install new transmission control module software, free of charge. GM will provide a special coverage program to cover the repair of transmissions that are identified by the remedy software as containing a defective control valve. Owner notification letters were mailed December 12, 2024. Owners may contact GM customer service at 1-888-988-7267, Cadillac customer service at 1-800-458-8006, GMC customer service at GMC 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N242454440.

• Latches/Locks/Linkages:Tailgate:Latch

  Feb 2024 · #24V060000

  General Motors, LLC (GM) is recalling certain 2020-2024 Chevrolet Silverado 2500, 3500, GMC Sierra 2500 and 3500 vehicles equipped with power-unlatching tailgates. The tailgate's electronic gate-release switch may short circuit due to water intrusion, which can result in the tailgate inadvertently unlatching while the vehicle is in park.

  Risk and fix

  Risk: An unlatched tailgate may open while driving and result in a loss of unsecured cargo, creating a road hazard and increasing the risk of a crash.

  Fix: Owners are advised to check that the tailgate is closed and latched before driving. Dealers will replace the exterior touchpad switch assemblies, free of charge. Owner notification letters were mailed May 17, 2024. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-800-462-8782. GM's number for this recall is N232426400.

• Service Brakes, Hydraulic:Power Assist:Electric:Control Module

  Sep 2021 · #21V758000

  NHTSA warning: park outside and away from buildings until fixed.

  General Motors, LLC (GM) is recalling certain 2021-2022 Chevrolet Silverado 2500, Silverado 3500, GMC Sierra 2500, and Sierra 3500 vehicles with electronic brake control modules (EBCM) replaced during vehicle assembly. The bolts that attach the brake pressure modulator valve (BPMV) assembly may not be properly tightened, which could fail to seal the two sub-assemblies and allow water intrusion.

  Risk and fix

  Risk: Water in the BPMV may cause an electrical short circuit and increase the risk of fire.

  Fix: Owners are advised to park outside and away from other structures until the recall repair is completed. Dealers will replace the BPMV assembly, free of charge. Owner notification letters were mailed on October 20, 2021. Owners may contact Chevrolet customer service at 1-800-222-1020 or GMC customer service at 1-800-462-8782. GM's number for this recall is N212349181.

• Seat Belts

  Dec 2020 · #20V811000

  General Motors, LLC (GM) is recalling certain 2020 Chevrolet Bolt EV and 2021 GMC Canyon and Sierra 1500, 2500 and 3500, Yukon, Yukon XL, Cadillac Escalade and Escalade ESV and Chevrolet Blazer, Camaro, Colorado, Equinox, Silverado 1500, 2500 and 3500, Suburban and Tahoe vehicles. Incorrect bolts may have been used at one or more fastening locations to secure the seat belts to the vehicle. If an incorrect bolt was used, the seat belt may not be properly attached to the vehicle.

  Risk and fix

  Risk: If a seat belt assembly is not properly attached to the vehicle, the seat belt may not properly restrain an occupant in the event of a crash, increasing the risk of injury.

  Fix: GM will notify owners, and dealers will replace the suspect bolts, free of charge. The recall began January 29, 2021. Owners may contact GMC customer service at 1-800-462-8785, Cadillac customer service at 1-800-458-8006, or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202322230.

• Seat Belts

  Dec 2020 · #20V792000

  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 and fix

  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.

Owner complaints by area

Reports owners filed with NHTSA. They aren't verified, and one complaint can mention more than one area. Tap an area to read the most recent ones.

• Electrical System12

  • Filed Aug 2026

    On XXX the 2021 Chevrolet Silverado was taken to Mayse Automotive Group at [XXX] dealership for the complaint of the key getting stuck in the ignition and unable to remove causing a safety and security risk. Service department found that the transmission control in column needed to be replaced. The park switch control was defective and providing incorrect data. Service department confirmed that many vehicles alike have needed same repairs. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

  • Filed Apr 2026

    Water entered tailgate through drainage hole in tailgate cap. The water then dripped on the tailgate switch causing it to short out. This short circuit caused my tailgate to open and close randomly without pressing any switches or buttons or key fobs. May tailgate has a small ding it it now from where it kept hitting the wall while parked in the garage. I took the truck to the dealership to get repairs done and was charged 308.88 for the tailgate switch and diagnosis that should have been under a recall for this truck. Safety Recall N232426400 Tailgate May Open Unexpectedly issued May 2024. I called the customer service number [XXX] to try and get reimbursed for the repairs and they told me there is no recall on my truck. I had this problem and it clearly states the year, make and model of my truck in the recall, but because my vin wasn't included I'm out of luck? I will attach all the info i have on this matter. Any help would be greatly appreciated. Thanks [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

  • Filed Feb 2026

    My 2021 chevy 3500hd diesel had the engine light come on and the service emissions system popped up in the info screen. It said in so many miles speed would be limited. I took it to the dealer and they said the def tank would need replaced because the tank wiring connector overheated and would cost me over 2k.

  • Filed Nov 2025

    Power unlatching tailgate opens unexpectedly (after big rain storm) The exact problem in this recall: Safety Recall N232426400 Tailgate May Open Unexpectedly However, my truck VIN wasn't part of the recall, even tho it shows it should be in the document above. I had to disconnect the tailgate switch myself to stop the tailgate from randomly opening while pulling a 5th wheel RV..... 3,000 miles from home. Just had it fixed at the dealer for 144, who said it wasn't coved under recall.

  • Filed Dec 2024

    Driving home from work 7/1/2024 approx 5:15PM Smelled burning smell, no noise or dash lights, thought it was another car. 1 minute later, heard a thump from under hood and "Charging System Failure" came on dash. Decided to take to Chevy dealer, which was 5 minutes away. Within next 2 minutes steering failed. As I came to next intersection, brakes failed, went thorough red light, luckily not hit by another vehicle. Coasted to stop and called tow service.Engine was still running until I turned it off. Had towed to local Chevy dealer. AC compressor had locked up, broken belt. Steering and brakes failed. Dealer agreed both failed, but would not list the brake failure on the invoice. I was originally invoiced 2900.00 to repair, even though truck had only 29244 miles. That was reduced to 1160.00. Was told it was 2 months past 36 month warranty. Engine was still under warranty, but AC, alternator, power steering and brakes, was not,. I had contacted GM which originally told me they would reimburse me for repairs and would mail me a check, I have the email. When check did not arrive after 2 months, I contacted my case worker again via email and phone. Could not get a response after about 6 attempts. When I called and finally got another person, I was informed they had changed their mind.

  • Showing the 5 most recent of 12.
• Power Train7

  • Filed Oct 2025

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that while driving approximately 65 MPH, the vehicle unexpectedly went into Low Power Mode, with the check engine and low power mode warning lights illuminated. The contact was able to restart the vehicle. The vehicle was taken to an independent mechanic, where DTC: P2706 and P2732 were retrieved, and the contact was informed that the valve body and certain components of the transmission required reprogramming. The vehicle was not repaired. The contact later received notification of NHTSA Campaign Number: 24V797000 (Power Train). The dealer was contacted but the vehicle was not diagnosed or repaired by the dealer. The manufacturer was not made aware of the failure. The approximate failure mileage was 146,000.

  • Filed Jan 2025

    This is regarding 24V797. A software update to "monitor" for transmission valve failure is not a resolution to a problem that could pose a sever risk to my safety on a very expensive truck.

  • Filed Nov 2024

    While towing my 5th wheel rv trailer, the rear wheels locked up numerous times while at highway speeds(60-70mph). Hope our didn't cause any internal/ structural damage to my trailer. Scheduled a service with the dealer(Gamblins Chevrolet, Enumclaw, WA) for them to diagnose. The dealer found no issue or cause. Left the dealer for the same thing to occur the following week. Brought back to the dealer for this issue and others to determine the torque converter had failed, dealer replaced converter, at a later date rear wheels locked up at highway speeds again. Been ongoing with no solution.

  • Filed Nov 2024

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated while driving at approximately 45 MPH, the brake pedal was depressed and extended to the floorboard, and the vehicle almost crashed into the rear of another vehicle. The contact later discovered that the rear driver’s side brake pad had been ejected from the vehicle. The vehicle was taken to the local mechanic who was unable to determine the cause of the failure. Additionally, the contact stated that the transmission erroneously shifted out of 4-WD while driving. The contact stated that the failure had occurred on several occasions. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 49,000. The VIN was not available.

  • Filed Jul 2024

    July 20, we were driving the 2021 3500HD to church w/our single axle trailer w/mower on it when we were stopped at a yield sign and proceeded to pull forward, our truck made a loud boom noise and immediately stopped. Warning lights on the dash began coming on, when the gas pedal was pressed it made a loud RPM sound of engine revving, following by barely coasting action. We were able to drift into the turn lane & get out of danger. We had to be towed to Capital Chevrolet bc something isn't functioning properly. Dealership said they believe it's transmission related and the power train warranty should cover repairs needed. We have tow receipt and gas receipts for rental vehicle.

  • Showing the 5 most recent of 7.
• Latches/Locks/Linkages6

  • Filed Sep 2026

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that while the vehicle was parked or while driving at undisclosed speeds, the tailgate unintendedly opened or closed. The failure was a recurring failure. The contact associated the failure with NHTSA Campaign Number: 24V060000 (Latches/Locks/Linkages); however, the VIN was not included in the recall. The manufacturer was contacted by phone and was made aware of the failure. The contact was informed that the repair was not free because the VIN was not included in the recall. The contact was referred to the NHTSA Hotline for assistance.

  • Filed Nov 2025

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that the tailgate occasionally opened and closed unintendedly. The failure had occurred several times. The dealer was contacted and notified of the failure. The vehicle was not diagnosed or repaired; however, an appointment was scheduled. The contact related the failure to NHTSA Campaign Number: 24V060000 (Latches/Locks/Linkages); however, the VIN was not included. The manufacturer was not informed of the failure. The failure mileage was 74,040.

  • Filed Oct 2025

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that while driving at various speeds, the tailgate inadvertently opened and closed. No warning light was illuminated. The contact stated that when the button to open the tailgate was pressed, the tailgate failed to function as intended. Upon further inspection, the contact related the failure to NHTSA Campaign Number: 24V060000 (Latches/Locks/Linkages). However, the VIN was not included in the recall. The vehicle was taken to the dealer, where it was diagnosed and determined that the electronic gate-release switch had short-circuited. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 8,611.

  • Filed Feb 2025

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that while the vehicle was in park(P), the tailgate independently opened during rainy or inclement weather. No warning light was illuminated. Upon further inspection, the contact related the failure to NHTSA Campaign Number: 24V060000 (Latch/Locks/Linkages); however, the VIN was not included in the recall. The local dealer was not contacted. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 34,000.

  • Filed Jan 2025

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that while the doors were unlocked, and the vehicle was idling or in motion; the rear tailgate independently opened and closed with an unknown warning light illuminated. The contact manually closed the tailgate and locked the doors to prevent the failure from reoccurring. Upon investigation, the contact linked the failure to NHTSA Campaign Number: 24V060000 (LATCHES/LOCKS/LINKAGES). The contact stated that the dealer and the manufacturer were notified of the failure and informed the contact that the VIN was not included in the recall and referred the contact to the NHTSA Hotline to report the failure. The vehicle was not repaired. The failure mileage was approximately 50,000.

  • Showing the 5 most recent of 6.
• Structure6

  1 involved a crash

  • Filed Apr 2026

    Water entered tailgate through drainage hole in tailgate cap. The water then dripped on the tailgate switch causing it to short out. This short circuit caused my tailgate to open and close randomly without pressing any switches or buttons or key fobs. May tailgate has a small ding it it now from where it kept hitting the wall while parked in the garage. I took the truck to the dealership to get repairs done and was charged 308.88 for the tailgate switch and diagnosis that should have been under a recall for this truck. Safety Recall N232426400 Tailgate May Open Unexpectedly issued May 2024. I called the customer service number [XXX] to try and get reimbursed for the repairs and they told me there is no recall on my truck. I had this problem and it clearly states the year, make and model of my truck in the recall, but because my vin wasn't included I'm out of luck? I will attach all the info i have on this matter. Any help would be greatly appreciated. Thanks [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

  • Filed Mar 2026

    The tailgate will go up and down when the vehicle is turned off and in park. It will also do this while driving the vehicle. * I notice there has already been a recall for this issue, but my VIN shows NO RECALLS

  • Filed Apr 2025

    Tailgate opens by itself. This happened 3 times in 2 hours while the vehicle was parked. I tow a 5th-wheel trailer. If this happens when towing it can cause a catastrophe.

  • Filed Nov 2024

    Electrical components are failing in the tailgate lock/unlock mechanism. The tailgate goes up and down on its own while in park. It will also go up and down on its own after the truck is off and unattended This started happening about a week ago. It is available for inspection upon request and has not been inspected by any agency yet. The tailgate could damage itself or other property randomly. It could also impact someone standing near it causing injury. There is a service appointment scheduled 3 days from now. There were no symptoms or warnings of a problem. The Chevy App actually says that all systems are ok.

  • Filed Nov 2024

    #N232426400-04: Safety Recall - Tailgate May Open Unexpectedly lists RPO code QT5 as the only applicable RPO code for the issue of tailgate opening unexpectedly. QT5 is for manual gate function with EZ lift, power lock release. The recall blames water intrusion into these vehicles’ tailgates that can come into contact with the electronic gate-release switch, potentially causing a short circuit, which may inadvertently unlatch and open the tailgate when in park. The correction is to replace the exterior touchpad switch assembly with part number 85734717. My vehicle has RPO code QT6, which is for power up/down gate function with power lock and release. That option uses the same exterior touchpad switch assembly with part number 85734717. My vehicle did exhibit the same problem of opening unexpectedly while in park. That exterior touchpad switch eventually stopped opening or closing the tailgate altogether, and occasionally the tailgate would get stuck in the closed position while a dash message would say it is open. When it was immobilized in the closed position neither the exterior switch, the interior switch, or the key fob would make the tailgate open. It's my opinion that my vehicle experienced the same root problem as is described in the recall with the exterior switch assembly short circuiting, and that RPO code QT6 units should be included in the recall.

  • Showing the 5 most recent of 6.
• Unknown or Other5

  • Filed Feb 2026

    My 2021 chevy 3500hd diesel had the engine light come on and the service emissions system popped up in the info screen. It said in so many miles speed would be limited. I took it to the dealer and they said the def tank would need replaced because the tank wiring connector overheated and would cost me over 2k.

  • Filed May 2025

    Our tailgate would open on its own intermittingly. We haul our fifth wheel camper and this could cause damage to the RV and our vehicle. There have been recalls on one year older trucks and one year newer but not for the 2021Chevrolet Silverado. A Chevrolet dearlership in Florida looked at it for us. They said cause : checked for codes and bulletins. Found code B153D. Completed circuit check. Also found tailgate hatch out of adjustment. Corrctionj: Rec. replace switch and adjust latch. We were charged $486.05 for this. We feel this should be a recall problem. Please advise.

  • Filed Nov 2024

    While towing my 5th wheel rv trailer, the rear wheels locked up numerous times while at highway speeds(60-70mph). Hope our didn't cause any internal/ structural damage to my trailer. Scheduled a service with the dealer(Gamblins Chevrolet, Enumclaw, WA) for them to diagnose. The dealer found no issue or cause. Left the dealer for the same thing to occur the following week. Brought back to the dealer for this issue and others to determine the torque converter had failed, dealer replaced converter, at a later date rear wheels locked up at highway speeds again. Been ongoing with no solution.

  • Filed Jul 2024

    July 20, we were driving the 2021 3500HD to church w/our single axle trailer w/mower on it when we were stopped at a yield sign and proceeded to pull forward, our truck made a loud boom noise and immediately stopped. Warning lights on the dash began coming on, when the gas pedal was pressed it made a loud RPM sound of engine revving, following by barely coasting action. We were able to drift into the turn lane & get out of danger. We had to be towed to Capital Chevrolet bc something isn't functioning properly. Dealership said they believe it's transmission related and the power train warranty should cover repairs needed. We have tow receipt and gas receipts for rental vehicle.

  • Filed Sep 2023

    Bought the truck in 2021. Replaced both outside mirrors during warranty. At about 44000 miles the passenger mirror malfunctioned again. The mirror resets to downward position and when you restart vehicle you need to readjust mirror each time. This is very dangerous especially while pulling the 5th wheel. Received a warning lite for a safety restraint failure. Took the truck to the dealer and was told the passenger side air bag was defective and it was a $1700 repair! Defective at 44000 miles? Are air bags only supposed to last such a short time? This is a serious safety issue that should be addressed and covered by all manufacturers warranties!

• Service Brakes5

  • Filed Oct 2025

    I was driving down the highway at speed limit when the dash lights came on and the truck started jerking went to a mechanic and he stated it was a fuel ejector after getting it replaced the issue still occurs often check engine light comes on and off and this the only transportation I have for work

  • Filed Dec 2024

    Driving home from work 7/1/2024 approx 5:15PM Smelled burning smell, no noise or dash lights, thought it was another car. 1 minute later, heard a thump from under hood and "Charging System Failure" came on dash. Decided to take to Chevy dealer, which was 5 minutes away. Within next 2 minutes steering failed. As I came to next intersection, brakes failed, went thorough red light, luckily not hit by another vehicle. Coasted to stop and called tow service.Engine was still running until I turned it off. Had towed to local Chevy dealer. AC compressor had locked up, broken belt. Steering and brakes failed. Dealer agreed both failed, but would not list the brake failure on the invoice. I was originally invoiced 2900.00 to repair, even though truck had only 29244 miles. That was reduced to 1160.00. Was told it was 2 months past 36 month warranty. Engine was still under warranty, but AC, alternator, power steering and brakes, was not,. I had contacted GM which originally told me they would reimburse me for repairs and would mail me a check, I have the email. When check did not arrive after 2 months, I contacted my case worker again via email and phone. Could not get a response after about 6 attempts. When I called and finally got another person, I was informed they had changed their mind.

  • Filed Nov 2024

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated while driving at approximately 45 MPH, the brake pedal was depressed and extended to the floorboard, and the vehicle almost crashed into the rear of another vehicle. The contact later discovered that the rear driver’s side brake pad had been ejected from the vehicle. The vehicle was taken to the local mechanic who was unable to determine the cause of the failure. Additionally, the contact stated that the transmission erroneously shifted out of 4-WD while driving. The contact stated that the failure had occurred on several occasions. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 49,000. The VIN was not available.

  • Filed Jun 2024

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that while driving at various speeds and attempting to depress the brake pedal, there was an abnormal sound coming from the brakes. There were no warning lights illuminated. The vehicle was taken to a local dealer where the brakes were replaced; however, the failure persisted. The local dealer advised the contact that it was a common manufacturer defect and that she needed to wait until parts became available to replace the brakes. The contact stated that the local dealer had not returned her call. The contact reached out to the local dealer recently and was informed that the vehicle was no longer under warranty and that the brakes could not be replaced free of charge. The contact also stated that while turning to the left or right, there was an abnormal sound coming from the tires. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 35,000.

  • Filed Oct 2020

    I GOT MY TRUCK IN MAY AND AFTER TWO MONTHS THE BATTERY WENT COMPLETELY DEAD WITHOUT WARNING SO HAD DEALERSHIP TOW IT TO SERVICE KEPT TWO WEEKS SAID IT WAS BATTERY. NOW SAME THING HAPPENED AGAIN. CALLED ROADSIDE ASSISTANCE FROM PHONE BECAUSE ON STAR WOULDN'T EVEN WORK. THEY COME OUT AND JUMPED IT. THE JUMP STARTED TRUCK BUT NOW PARKING BREAK WON'T RELEASE AND I HAVE A SERVICE LIGHT ISSUE,, STILL WAITING FOR CHEVY TO OPEN TO HAVE IT TOWED AGAIN. IS ANYONE ELSE DEALING WITH PROBLEMS? I WAS TOLD BY THE DEALER LAST TIME THAT THE ROCKY RIDGE ADDITIONS ARE.

• Fuel/Propulsion System4

  • Filed Feb 2026

    Service engine light kept coming on the dash, and the code came back to a faulty DEF heater. My truck had a reduced power countdown on the dash indicating the truck was going go to into limp mode after x amount of miles. On warmer days the code would go away and there would be no reduced power. The vehicle was diagnosed at a GM dealership and confirmed the DEF heater was bad, but was notified that there is a bulletin with GM for this issue occurring in many other diesel trucks. My safety was put at risk due to the rapidly changing reduced speed milage, at any point it could drop from 100miles, to 10 miles until reduced speed. This could cause an instant car accident while driving if the truck were to randomly slow down to a speed much slower than the speed limit. IE- driving on the north way (65 speed limit) and having the speed drop to 5mph unexpectedly when you just had over 100 miles to reduced speed.

  • Filed Feb 2026

    My 2021 chevy 3500hd diesel had the engine light come on and the service emissions system popped up in the info screen. It said in so many miles speed would be limited. I took it to the dealer and they said the def tank would need replaced because the tank wiring connector overheated and would cost me over 2k.

  • Filed Dec 2024

    Injector #4 connector harness issue- Known issue on the 6.6L duramax. Driving with my children for Christmas pickup and power reduction occurred while passing another car on the road. Causing us to hit the breaks as the truck wouldn’t allow us to pass timely. Known harness issue by GM and instead of covering I had to pay to have a new connector spliced in. Multiple warning lights. Check engine, Emissions warning, Reduced power, Traction control, parking brake

  • Filed Jul 2022

    Check engine light came on followed almost immediately with an Onstar warning to service the engine and transmission within 7 days. Took truck to dealer. They diagnosed problem was fuel system contamination. Hole was found on the inner mesh liner of the fuel filter which allowed water and a sludge like material to get into the fuel system.

• Engine3

  • Filed Nov 2025

    My 2021 Chevy Silverado 3500 [XXX] Motor began requiring a quart of oil every 3-4 weeks. I took my vehicle to a GM dealer in October 2024 and the stated the couldn't find any issues. Fast forward to December 2024 my motor began reading low compression and saying stop the vehicle. I took the vehicle back and pressured them to find out whats wrong with the truck as I only have 76,000 miles and I have performed all of the necessary maintenance. I even have a Chevrolet Platinum protection plan for warranty coverage. I have gotten the run around for months and I have yet to get my vehicle repaired. After taking my truck to a certified 3rd party the verified that the lifters failed and the motor would likely need to be replaced or rebuilt. The mechanics reported this Information to the Chevrolet warranty company and the stated the refuse to provide and repairs unless I produce oil change receipts or return the vehicle back to a dealership and pay for the dealer to tear the motor down. PLEASE HELP ME!!! Im stuck paying 819 a month for a truck I haven't driven regularly since December 2024. Please please please help me Sincerely [XXX] General Motors [XXX] 2021 3500 hd wt 4x4 Case # 9-XXX [XXX] I have a 2021 chevy 3500 lt (dually) Been having issues with a rough idle so I figured to replace the plugs, coil packs and wires as my truck just hit 70,000 miles. After doing the full tune up nothing changed, so I scheduled an appointment with my local chevy dealership. They kept my truck for about a week and never completed the diagnosis. I picked the truck back up and took it to another chevy dealer and the told me after a week or so that I had lifter issues and the truck would probably need a new motor. The truck seemed a little sketchy from the gate in the first 50k miles it consumed oil like it was a ol 250k mile chevy.... the alternator went out at around 50k miles and the fuel efficiency would be 6-8 mpg at best..... INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

  • Filed Oct 2025

    I was driving down the highway at speed limit when the dash lights came on and the truck started jerking went to a mechanic and he stated it was a fuel ejector after getting it replaced the issue still occurs often check engine light comes on and off and this the only transportation I have for work

  • Filed Sep 2021

    Was driving my 3500 (an 8000# truck capable of towing 20k#) and suddenly the vehicle lost power and steering, forcing me to the shoulder of a curvy mountain road, going downhill. Truck then started blinking lights and telling me to restart. upon restart, the truck would not engage the transmission. Truck was in drive but the motor was just rev'ing. I turned truck off and then back on and it seemed to return to normal. Am not comfortable driving truck at this time. GM has been notified of the issue, and, has not diagnosed an issue, as of this writing.

• Steering2

  • Filed Aug 2026

    On XXX the 2021 Chevrolet Silverado was taken to Mayse Automotive Group at [XXX] dealership for the complaint of the key getting stuck in the ignition and unable to remove causing a safety and security risk. Service department found that the transmission control in column needed to be replaced. The park switch control was defective and providing incorrect data. Service department confirmed that many vehicles alike have needed same repairs. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

  • Filed Dec 2024

    Driving home from work 7/1/2024 approx 5:15PM Smelled burning smell, no noise or dash lights, thought it was another car. 1 minute later, heard a thump from under hood and "Charging System Failure" came on dash. Decided to take to Chevy dealer, which was 5 minutes away. Within next 2 minutes steering failed. As I came to next intersection, brakes failed, went thorough red light, luckily not hit by another vehicle. Coasted to stop and called tow service.Engine was still running until I turned it off. Had towed to local Chevy dealer. AC compressor had locked up, broken belt. Steering and brakes failed. Dealer agreed both failed, but would not list the brake failure on the invoice. I was originally invoiced 2900.00 to repair, even though truck had only 29244 miles. That was reduced to 1160.00. Was told it was 2 months past 36 month warranty. Engine was still under warranty, but AC, alternator, power steering and brakes, was not,. I had contacted GM which originally told me they would reimburse me for repairs and would mail me a check, I have the email. When check did not arrive after 2 months, I contacted my case worker again via email and phone. Could not get a response after about 6 attempts. When I called and finally got another person, I was informed they had changed their mind.

• Air Bags2

  • Filed Jul 2024

    Tilt sensors, upper air bags deployed almost causing a catastrophic crash. I did report to gm but I have not received answers yet. Vehicle deployed air bags without warning.

  • Filed Sep 2023

    Bought the truck in 2021. Replaced both outside mirrors during warranty. At about 44000 miles the passenger mirror malfunctioned again. The mirror resets to downward position and when you restart vehicle you need to readjust mirror each time. This is very dangerous especially while pulling the 5th wheel. Received a warning lite for a safety restraint failure. Took the truck to the dealer and was told the passenger side air bag was defective and it was a $1700 repair! Defective at 44000 miles? Are air bags only supposed to last such a short time? This is a serious safety issue that should be addressed and covered by all manufacturers warranties!

• Tires1

  • Filed Sep 2025

    With 33k miles on the original tires on my 2021 Chevrolet Silverado 3500HD. Driver's side rear ire self destructed going down the highway at 70mph. Was not towing at the time. LT275/65R20 126/123S E @ 80psi

• Fuel System1

  1 involved a fire

  • Filed Jul 2024

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that while driving at approximately 45 MPH, he noticed smoke coming from the rear of the vehicle. The contact mentioned that the smoke would become more aggressive as the accelerator or brake pedal was depressed. The vehicle caught on fire however the origin was unknown. The contact and his family exited the vehicle safely and discovered unknown fluid emitting from the rear of the vehicle. The contact used a fire extinguisher to attempt to extinguish the fire however the fire kept returning a total of 4 times. The fire department was contacted and extinguished the fire. A fire report was not filed. A police report was filed however the police report number was unknown. No injuries were sustained. The vehicle was destroyed and burned to the frame. The manufacturer was notified of the failure. The failure mileage was 15,521.

• Diesel1

  1 involved a fire

  • Filed Jul 2024

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated that while driving at approximately 45 MPH, he noticed smoke coming from the rear of the vehicle. The contact mentioned that the smoke would become more aggressive as the accelerator or brake pedal was depressed. The vehicle caught on fire however the origin was unknown. The contact and his family exited the vehicle safely and discovered unknown fluid emitting from the rear of the vehicle. The contact used a fire extinguisher to attempt to extinguish the fire however the fire kept returning a total of 4 times. The fire department was contacted and extinguished the fire. A fire report was not filed. A police report was filed however the police report number was unknown. No injuries were sustained. The vehicle was destroyed and burned to the frame. The manufacturer was notified of the failure. The failure mileage was 15,521.

• Forward Collision Avoidance1

  • Filed Feb 2023

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated while driving 65 MPH and above, the radar sensors failed to function intermittently. There was no warning light illuminated. The vehicle was taken to the dealer to be diagnosed. The dealer found no cause for the failure. The contact was informed to replace the sensors. The manufacturer was notified of the failure, but no assistance was provided. The vehicle was not repaired. The failure mileage was approximately 7,000.

• Lane Departure1

  • Filed Feb 2023

    The contact owns a 2021 Chevrolet Silverado 3500. The contact stated while driving 65 MPH and above, the radar sensors failed to function intermittently. There was no warning light illuminated. The vehicle was taken to the dealer to be diagnosed. The dealer found no cause for the failure. The contact was informed to replace the sensors. The manufacturer was notified of the failure, but no assistance was provided. The vehicle was not repaired. The failure mileage was approximately 7,000.

• Exterior Lighting1

  • Filed Mar 2021

    THE NEW GM 2021 TRAILER LIGHTING MODULE AND/OR SYSTEM IS DEFECTIVE. IT FAILS A PRE-CONNECTION TEST WITH TESTER, GIVES "CHECK TRAILER WIRING" WARNING ON DASH WITHOUT A TRAILER CONNECTED AND TURNS OFF ANY TRAILER LIGHTING CONNECTED WITHOUT WARNING ON THE ROAD, WITHOUT BLOWING A FUSE. THIS PROBLEM IS MUCH LIKE THE TSB REPORT #20-NA-198 FOR EARLIER MODELS. THIS ISSUE WAS ADDRESSED BY THE DEALER BY REPLACING THE MODULE, BUT THE PROBLEM HAS RE-OCCURRED WHILE ON THE ROAD CAUSING A ROAD SAFETY ISSUE (NO TRAILER LIGHTING), SOME TIMES WITHOUT WARNING. THE DEALER DOESN'T KNOW WHAT ELSE TO DO AT THIS POINT.

Safety ratings

NHTSA 5-Star Safety Ratings from government crash tests. Ratings can differ by cab style and 2WD/4WD.

NHTSA hasn't published star ratings for this truck. Many heavy-duty pickups aren't included in NHTSA's crash-test program, so this doesn't mean the truck is unsafe.