855 of the
11,236 complaints filed about the Chevrolet Blazer
are about the transmission —
8% of everything owners reported.
The worst model year for it is 1997.
855
Complaints
8%
Share of all complaints
21
Crashes
17
Fires
Transmission & Drivetrain complaints by model year
The car is not sensing that it is in park when it is. When I place it in park and turn the car off it dings and says shift into park however it already is in park. Therefore the car will not turn off. I had to jiggle the shift or turn the car on, reverse then go forward then park to get it to register. This has taken up to 10 minutes and it’s getting worse. This is a known issue that is referenced in GM Technical Service Bulletin 19-NA-206.
NHTSA complaint #11758760 — an unverified report by a vehicle owner.
Sudden catastrophic drive train failure while driving. Car stopped instantly and was totally immobilized. It had to be dragged onto a flatbed tow truck. It is at dealership now for evaluation.
NHTSA complaint #11753684 — an unverified report by a vehicle owner.
The contact owns a 2021 Chevrolet Blazer. The contact stated that while driving at an undisclosed speed, the accelerator pedal was depressed, and the transmission was slipping gears before the vehicle lost motive power. The contact stated that the vehicle failed to drive forward or move while in reverse. The check engine warning light was illuminated. The vehicle was towed to the residence. The contact, who was an independent mechanic, diagnosed the failure as a clutch solenoid failure. The contact stated that the transmission needed to be replaced. The vehicle was not repaired. The contact referenced an unknown recall; however, the VIN was not associated with a recall related to the failure. The dealer was made aware of the failure but provided no assistance. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 100,000.
NHTSA complaint #11751752 — an unverified report by a vehicle owner.
I have been smelling engine coolant for some time and found a leak on the drivers side top seam where the aluminum meets the plastic tank on the radiator. This is a known problem with 2019=2026 Chevy Blazers by GM and it still hasn't been resolved. After researching, I have found numerous Blazer owners that have this same issue and some are on 3rd and 4th radiator replacement. I am afraid to drive the vehicle due to the leak that could leave me and my family stranded on the side of the road. I am also concerned about a major leak or seam separation that could allow a large amount of coolant out that could get on the tires and cause loss of vehicle control as a result. Also, the leaking coolant is a hazard to any animals that are around as the coolant puddles under my vehicle after driving. At this point, the Blazer is running hotter and I had to add coolant. I just called to price a new radiator...$450 and install...$1,025...that isn't a cost I should have to take on with GM knowing about this issue for years.
NHTSA complaint #11750535 — an unverified report by a vehicle owner.
Last year I was heading to heading to [XXX] in XXX when I pushed on the brakes on my 2020 Chevy blazer my brakes were working but the steering wheel was shaking weird like I was hard on the brakes but I was tapping them slowly earlier this year right before I had transmission flush at fox Chevy in Caledonia I noticed before two weeks of bringing it in I was near a traffic light slowing down it went hard shift down and when I was not moving in notice it jerked forward when at idle and the light like it was rear ended I feel like this is a safety concern of that happening after the transmission flush for two months after doing the acceleration is slipping I feel like there should be a recall for torque and transmission recalls for the 2020 Chevy blazers I really love this blazer owned for 4 years now I feel like it would be a safety for the public and nationwide INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11749874 — an unverified report by a vehicle owner.
The thermostat malfunctioned causing an error message regarding “steering assist is reduced”. When I parked and turned off, the engine fan continued to run. When car was restarted, the temp gauge inside was stuck at C. Took to dealership and they assessed. They repaired the thermostat under power train warranty, however there was a crack in the radiator (top) resulting in the need for a new radiator. This vehicle had 35,000 miles on it. Upon research online, it seems there are MANY people who have had this same issue and worse. It appears cars produced during COVID era are most affected. Chevy refused to warranty the issue. The dealership offered a small cost reduction (due to our loyalty). The thermostat and the radiator issues seem to be well known by Chevy, they just refuse to accept responsibility. Now we are out thousands of dollars on a basically “new” vehicle.
NHTSA complaint #11745926 — an unverified report by a vehicle owner.
The contact owns a 2023 Chevrolet Blazer. The contact stated that while driving 10 MPH and pulling into a parking lot, the sun gear and the drive shaft fractured. The vehicle became inoperable. The vehicle was pushed to a safe place. The check engine warning light illuminated after the failure. The contact associated the failure with NHTSA Campaign Number: 23V172000 (Power Train). The vehicle was towed on a flatbed to the local dealer. The vehicle was not diagnosed or repaired. The dealer provided an estimate for the transmission replacement. The manufacturer was contacted and confirmed that there was no recall coverage on the VIN for the failure. The manufacturer referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 107,000.
NHTSA complaint #11745894 — an unverified report by a vehicle owner.
The contact owns a 2023 Chevrolet Blazer. The contact stated that while driving at various speeds, the vehicle hesitated while depressing the accelerator pedal. There was no warning light illuminated. The vehicle was taken to the dealer on several occasions to be repaired; however, the dealer was unable to duplicate the failure or determine the cause of the failure. The contact stated that the dealer performed a transmission fluid flush; however, the failure persisted. The manufacturer was notified of the failure but offered no assistance. The vehicle was not repaired. The failure mileage was approximately 25,000.
NHTSA complaint #11746026 — an unverified report by a vehicle owner.
I am submitting this complaint regarding the transmission in my 2020 Chevrolet Blazer. My vehicle has fewer than 100,000 miles and has experienced significant transmission failure symptoms, including hard shifting, jerking during acceleration, RPM fluctuations, slipping, loss of normal power, and inability to safely reach highway speeds. The vehicle struggles to accelerate properly and at times will not shift correctly into higher gears. Diagnostic trouble codes related to transmission operation have been present, including pressure control solenoid and transmission control faults. Repairs have already been attempted, including replacement of transmission-related components, but the transmission continues to malfunction. Through online owner groups, forums, and discussions with other Chevrolet Blazer owners, I have found numerous reports from owners experiencing similar transmission problems in 2019-2022 Chevrolet Blazers. Many owners report transmission slipping, harsh shifting, torque converter issues, valve body failures, pressure control solenoid failures, and complete transmission replacement at relatively low mileage. These failures create a serious safety concern because the vehicle may hesitate, lose power, fail to accelerate properly when entering traffic, or be unable to maintain safe highway speeds. Drivers and passengers are placed at risk when a vehicle cannot respond normally during merging, passing, or other traffic situations. Owners are frequently being quoted between $7,000 and $12,000 for transmission replacement or repair despite the vehicles being relatively new and often having less than 100,000 miles. Many consumers believe these failures indicate a widespread defect rather than normal wear and tear. I request that NHTSA investigate transmission failures in the 2020 Chevrolet Blazer and related model years to determine whether a manufacturing or design defect exists and whether a recall or other corrective action is warranted.
NHTSA complaint #11744816 — an unverified report by a vehicle owner.
BROUGHT MY CAR TO CHEVROLET CENTER IN WINTER HAVEN FLORIDA BECAUSE I HAD 2 DIAGNOSTIC CODES SHOW UP WITH A CHECK ENGINE LIGHT, THE CODES WERE (U1345: Indicates a communication fault on the LIN (Local Interconnect Network) Bus, usually tied to modules like the active grille shutters, cooling fans, or charge air cooler (CAC) pump.U0632: Indicates lost communication specifically with Cooling Fan 1.) THE DEALERSHIP TOLD ME THEY DIDN'T FIND ANY CODES IN THE SYSTEM AND THEY TRIED TO CHARGE ME $165 FOR A DIAGNOSTIC FEE. RIGHT AFTER I LEFT THE DEALERSHIP I WAS HAVING THE SAME CODES POP UP, WITH THE CHECK ENGINE LIGHT AND MY CAR WAS OVERHEATING. CHEVROLETS ECM/PCM WARRANTY IS 8 YEARS OR 80,000 MILES.
NHTSA complaint #11744030 — an unverified report by a vehicle owner.
I am submitting this complaint regarding my 2020 Chevrolet Blazer and what appears to be a widespread cooling system defect. My vehicle has developed a coolant smell outside the vehicle, which raises concerns about a coolant leak from the radiator. After researching the issue, I discovered that numerous Chevrolet Blazer owners have reported similar coolant-related problems, including radiator failures, coolant leaks, and persistent coolant odors. These complaints are widely discussed across online forums, social media, and owner groups. General Motors appears to be aware of this recurring issue, yet many owners continue to experience failures within and outside of warranty coverage. The coolant smell is concerning because it may indicate a leak within the cooling system, which could lead to overheating, engine damage, loss of vehicle reliability, and potential safety risks while driving. Owners should not be experiencing major cooling system failures on relatively modern vehicles. I request that NHTSA investigate the cooling system and radiator issues affecting the 2020 Chevrolet Blazer and determine whether a defect exists that warrants a recall or other corrective action. The number of similar complaints suggests this may be a systemic issue rather than isolated incidents. General Motors should be held accountable for addressing this widespread problem and providing a permanent repair solution for affected owners. Thank you for your attention to this matter.
NHTSA complaint #11743467 — an unverified report by a vehicle owner.
Engine temp gauge stops working causing the air to stop working and the cooling fan to rev to highest rpm. Also a warning that the steering assist is reduced. Eng check light comes on with a code P0208. This a known problem with an extended service # (N242484760) but only if your vin is listed. All vehicles with this problem should be covered
NHTSA complaint #11740390 — an unverified report by a vehicle owner.
The transmission (powertrain) developed a delay when shifting into reverse, followed by harsh engagement. The condition worsened over time and resulted in a complete loss of reverse. The vehicle will not move when shifted into reverse. This creates a safety risk when parking, backing out of spaces, or maneuvering in traffic, as the driver cannot safely control vehicle movement. The issue occurred at approximately 89,000 miles under normal driving conditions. No warning lights were present prior to failure. The problem was reported to a dealership and diagnosed as a transmission failure. The condition is reproducible and ongoing. I was also informed that multiple vehicles of the same model were experiencing similar transmission issues at the same time. The failure limits safe operation of the vehicle and increases risk in situations where reverse movement is required.
NHTSA complaint #11733441 — an unverified report by a vehicle owner.
My engine coolant temperature sensor failed. Replaced it and still not fixing the issue. This takes my steering assist away as they are all interlinked? I have seen on forms this is a common issue. This has the potential to blow up my engine, I’m not sure how this is not a recall with so many 2020-2026 blazer owners having the same issue.
NHTSA complaint #11732623 — an unverified report by a vehicle owner.
Once I turn the vehicle off, there is a loud sound coming from the engine area that sounds like a fan. Then the first incident of the fan ongoing after the vehicle was powered off, a battery light was on the internal driver dashboard and stayed on. The battery was recently replaced during 2026 so the battery should not be anywhere near dead, dying, or needing to be checked
NHTSA complaint #11730609 — an unverified report by a vehicle owner.
| Issues first appeared recorded on 3/9/2026, while odometer read 49,663 miles. Check engine light was caused by error codes P0128 and P01F0. This causes the following issues: * Check engine light to appear on the dashboard. * Engine temperature gauges to be unreliable at times or completely non functional at others, as it will constantly read the engine temperature "Cold". * Air conditioning unit to become unreliable at times or completely non functional at others, and only blow hot air. * Radiator fan will be stuck running at max speed despite current engine temperature. * A "Reduced Steering Assist" message will periodically appear on the dashboard. * A "Service ESC" message will periodically appear on the dashboard. * Remote start will becomes non functional. | Car was taken to a license Chevrolet dealership and had full thermostat housing and thermostat sensors replaced. Dealership confirmed all replaced parts are working correctly and as intended. After picking up the vehicle from the dealership, and driving car for roughly 30 miles, the check engine light appeared on the dashboard again causing all previous issues to return. | Several other Chevy Blazer 2020 owners have complained of the same issue online, and in forums such as: [XXX] . | INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11729613 — an unverified report by a vehicle owner.
Shift to Park issue: Known issue where the car fails to recognize it is in Park, preventing it from shutting off. Electronics: Potential blanked-out display screens, USB port issues, and malfunctioning cameras. Steering Assist: Restricted, temperature gauge goes to cold and radiator fan blows hard. I have to unplug negative cable to battery and reconnect and everything goes back to normal.
NHTSA complaint #11729329 — an unverified report by a vehicle owner.
I was driving to work as I normally do and work is only 15 miles away from home I get to work turn into the parking lot stop to scan my badge and I hear knocking noise I thought it was coming from the truck in front of me but after he moved on I still heard the noise and I found a parking spot as soon as I could and the engine light on the dash came on and the motor that was knocking is definitely my Blazer with only 11,222 miles on it. I always keep up on my vehicles maintenance in fact I just had the oil changed at Ray Skillman Gm Dealership2/16/26 it had 10,960 miles on it. Before that I had the oil changed at Ray Skillman 08/20/25 it had 7,720 miles on it then and before that. The very first oil change 22/ may /25 the mileage was 5,354 on it was at Hare Chevrolet where I purchased this Blazer RS Brand new it had 34 miles I always get the oil changed when it gets to 25%
NHTSA complaint #11725131 — an unverified report by a vehicle owner.
Just took my car to the Chevy dealership today and had them go over the car because I keep getting the message steering assist has been reduced and the fan is constantly running at the highest speed and it also makes it where I can not use the a/c or heat in the car! I don’t know the code off hand but it has something to do with the cam shaft and the thermostat for the antifreeze! From what Chevy told me today it is a $9000 job to tear down the left side of the engine because the camshaft carrier gasket is leaking oil! Which is probably why that code is popping up. Or from what I was told today it could be from the battery which I believe they were trying to shift blame. Either way this camshaft stuff really needs to be investigated!!
NHTSA complaint #11724826 — an unverified report by a vehicle owner.