2021 Chevrolet Trailblazer Powertrain (other) Problems

Dear Chevy, I am reaching out to you again because I am desperately requesting immediate assistance with my vehicle, which has now become an extremely serious and dangerous safety concern. On Friday, [XXX], I had my vehicle towed to the dealership because of the ongoing mechanical issues I have been experiencing. I was advised that the repairs would cost $877, which included a battery replacement and new sensors. I paid for these repairs and picked up my vehicle on Wednesday, September 2, 2026, believing that the issues had finally been addressed. Unfortunately, within approximately one hour of leaving the dealership, my check engine light came back on. When I arrived home, the key became stuck in the ignition. I immediately contacted the dealership and requested to speak with a Service Manager. I made this request approximately five separate times, yet I was unable to speak with a Service Manager until Friday, September 4, 2026, when I finally spoke with Matt. The situation has now escalated into an extremely dangerous and potentially life-threatening safety issue. On Sunday, [XXX], while driving on the [XXX] in Chicago, my vehicle completely shut off twice while I was actively driving. There were no warning sounds, no dashboard warning codes, and no indication that the vehicle was about to shut off. My vehicle suddenly lost power while I was on a busy expressway, creating an extremely dangerous situation and nearly causing a major accident/pileup. I genuinely feared for my life. A vehicle that unexpectedly shuts off while traveling at highway speeds is not something I can safely continue driving. After this occurred, I had the vehicle towed to my home. I later attempted to start it, and the vehicle did start; however, the key became stuck in the ignition again. This problem has been ongoing for over a year, and I have repeatedly and desperately asked for these issues to be properly diagnosed and repaired. I have already INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 5

NHTSA ID

11762612

Incident

Sep 6, 2026

Original Owner of 2021 Chevy Trailblazer LT. Purchased new in April 2021. Vehicle has a history of major powertrain issues, starting with Check Engine light during its first year of ownership, culminating in a complete turbocharger replacement in December 2025. This only as a result of my research, after many visits to dealership trying to diagnose the issue. The check engine was consistently illuminated in the vehicle 2021-2025. 9 days ago while traveling the vehicle, experienced sudden oil pressure loss, and stalling risks, displayed a hard warning “ENGINE OIL PRESSURE LOW. STOP ENGINE”. On Star provided me with a diagnostic code of P0521, pointing to an engine oil pressure sensor malfunction. Apparently another widely known issue with this engine, there are TSBs stating after repair the code will return and Software Update required. Extended warranty has expired, dealership as well as GM corporate unwilling to provide any assistance with cost of diag, repairs, etc, leaving myself and disabled dependent stranded. Vehicle since purchase has been exclusively serviced through the purchasing dealerships service center. Maintenance regularly maintained. Service management has admitted knowledge of this issue with this engine, still reluctant to provide any additional assistance, informed me I’m on a waitlist for a possible loaner vehicle 4-6 weeks from now. There are several TSBs on this engine surrounding this issue. Apparently there is a known defect with the engine oil pump, cam shaft, evap purge pump. Strong possibility could be a result of the Turbo replacement, debris from that failing turbo could have blocked the oil system, causing starvation.

NHTSA ID

11761820

Incident

Aug 26, 2026

"shift to park" issue on a 21 traiblazer causing your car to not being able to shutdown entirely meanwhile the shift is perfectly on Park.

NHTSA ID

11753767

Incident

Oct 9, 2025

My trailblazer will not shift properly into drive from park or reverse. GM calls this a "loss of forward motion" or "delayed forward engagement" in their service bulletin TSB-24-NA-009. It is a safety issue because you never know when or how long the vehicle will take to engage and allow forward movement. This causes issues when leaving a parking spot or a driveway, especially on busy roads. If the car will not move forward, my family is stuck in the road until it finally engages into gear and allows forward movement. When this occurs, the vehicle engine will shutter and not allow any forward movement. I usually have to move the drive selector back to park and back to drive again. This creates an immediate and unreasonable safety risk because the vehicle will not move for several seconds while I am sitting in traffic. This generates a P2714 code. I had the car looked at by a GM dealer as well as an independent transmission repair shop and both indicate it will likely need a new transmission. GM is fully aware of the defect and has issued a service bulletin, TSB-24-NA-009 to instruct dealers how to diagnose and repair the problem. The bulletin proves a widespread engineering or manufacturing flaw exists. However, GM is treating this as a maintenance issue rather than the severe safety hazard that it is. It is my understanding, GM has since abandoned this transmission on the newer models, further indicating that GM knew these transmissions were not designed well. I am requesting the NHTSA office cross-reference my complaint with GM TSB-24-NA-009 and upgrade the component defect to a mandatory, manufacturer-funded safety recall before it causes a collision or fatal injury. Thank You

NHTSA ID

11752367

Incident

Jun 30, 2026

Vehicle has 67,000 miles and suffered a catastrophic CVT transmission failure, documented by dealership diagnostic code P2714. The transmission severely slips and exhibits a dangerous 15-second delay to engage forward gear after shifting into Drive. More critically, the vehicle suffers from unpredictable engine stalling. The car completely shut down and stalled in traffic while trying to accelerate into a driving lane after shifting. The vehicle did not trigger any dashboard safety warnings, limp mode, or "Reduced Engine Power" messages prior to shutting down, causing an un-warned loss of motive power on a public road. This creates an immediate, severe risk of a high-speed rear-end collision. General Motors has acknowledged internal CVT chain slippage and hydraulic failure points in Technical Service Bulletins 24-NA-009 and PIP6033 but has not issued a safety recall.

NHTSA ID

11750836

Incident

Jul 1, 2026

I am reporting a serious safety issue with my 2021 Chevrolet Trailblazer related to transmission failure. The vehicle has approximately 83,000 miles. While driving, the vehicle experiences a sudden loss of power when attempting to accelerate. In some instances, the vehicle has stalled or shut off while I was actively driving, creating a dangerous situation, especially when merging into traffic or driving through intersections. The issue is intermittent but has become more frequent over time. The vehicle does not respond properly when the accelerator is pressed, and there is a noticeable delay or complete lack of power. At times, the vehicle will not move as expected, which poses a significant safety risk. Diagnostic codes associated with this issue include P2714 and P0700, which indicate a transmission-related malfunction. I have been advised that the vehicle requires a full transmission replacement. This failure occurred at relatively low mileage for a major powertrain component, and I am concerned this may indicate a broader defect. The stalling and loss of power create a hazardous driving condition that could result in an accident. I am submitting this complaint to report a potential safety defect and to request further investigation into this issue.

NHTSA ID

11734472

Incident

Jan 13, 2026

My transmission is defective and past 60,000 miles but only a little. I had a diagnosis and it needs replacing like many of these trailblazers in the ongoing lawsuit. I cannot pay for it and it should not be broken!

NHTSA ID

11723367

Incident

Mar 10, 2026

My 2021 Chevrolet Trailblazer has a defect in the gear shifter system that intermittently fails to recognize when the vehicle has been shifted into “Park.” When this occurs, the vehicle displays a persistent “Shift to Park” warning message and prevents the engine from being turned off or the vehicle from being locked. This malfunction creates a safety and consumer concern, as I am unable to exit and secure the vehicle and am forced to remain inside or leave the vehicle running and unattended. The issue interferes with normal vehicle operation and poses potential safety risks, particularly in situations where I need to quickly power down, exit, or secure the vehicle. After a quick internet search, this issue appears to be affecting multiple others with the same vehicle (2021-2023). A prior lawsuit against GM also resulted in a settlement and recall for older model Trailblazers, but unfortunately did not include the newer models that are experiencing the same known issue. • Gear shifter system is malfunctioned, specific reason and/or part is unknown. Vehicle is available for inspection upon request. • Safety risks noted above. • Problem has been confirmed over the phone and via text by local Chevrolet dealership. Only solution offered was to pay over $650+ for a fix that is not guaranteed to fully resolve the error. • Vehicle or component has not been physically inspected by manufacturer, police, insurance reps, or others. • No warning lamps, messages, or other symptoms occurred prior.

NHTSA ID

11708387

Incident

Jul 1, 2025

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while attempting to park, the vehicle failed to shift into park properly, and the message “Vehicle Not in Park” was displayed. The contact stated that several attempts were needed before the transmission was able to be shifted into park. The vehicle was taken to the dealer, where it was diagnosed and determined that the shifter gear assembly had failed and needed to be replaced. The vehicle was repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 40,000.

NHTSA ID

11696558

Incident

Oct 30, 2025

Mileage

40,000 mi

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that after reversing, the transmission was shifted to drive (D), but the vehicle failed to immediately recognize the selected gear. The check engine warning later illuminated. The vehicle was taken to an independent mechanic, who determined that the under boost, transmission control module, and transmission control solenoid had failed, and there was a loss of communication with the radio and loss of communication with the telematic control module. The mechanic advised the contact to take the vehicle to the dealer for assistance. The vehicle was not repaired. The manufacturer was made aware of the failure and advised the contact to report the failure to the NHTSA Hotline. The failure mileage was approximately 42,000.

NHTSA ID

11693768

Incident

Aug 31, 2025

Mileage

42,000 mi

My vehicle displayed a Shift to Park message even though I was already in Park. I could not turn off the engine, I could not lock my car. I had to go back into Drive and then Park mode and wiggle the shifter multiple times to get it to recognize Park and turn off the car. This is now happening almost every time I drive the car. I did an internet search to see how to rectify the problem only to find that this exact issue has plagued GM vehicles for a decade and they still have not chosen to rectify the faulty part. There have been multiple recalls and class action lawsuits for the SHIFT TO PARK fault but not for my vehicle year YET! There are many Trailblazer owners who are experiencing this exact issue (on online forums) and GM so far is refusing to take responsibility and issue a recall to fix the issue for owners and also to stop using this faulty system in their cars. I have reached out to GM about this multiple times the past few weeks and requested they pay for diagnostic and fix the problem because it is a common and known problem with GM vehicles but they want me to pay for it myself and the repair and then they may decide to help out - unacceptable in my opinion. To be honest there needs to be a recall NOW and GM needs to be forced to change the components in all new models to stop this happening in future models going forward. This problem can cause the car battery to drain, it can cause the vehicle to roll away if it’s not recognizing it’s in Park. Thankfully that hasn’t happened to me but others have had this happen. Not being able to shut the engine off or lock my car is a problem. This is a safety issue that needs addressing. I have lots of messages and communication from General Motors which I have attempted to attach the screenshots with the photo below but get an error message on the upload page.

NHTSA ID

11683489

Incident

Aug 12, 2025

The contact owns a 2021 Chevrolet Trailblazer. While the contact's wife was attempting to park the vehicle, the shift to park warning light illuminated. The dealer was made aware of the failure; however, the vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The contact was informed of an undisclosed recall; however, the VIN was not under recall. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 79,000.

NHTSA ID

11683398

Incident

Aug 14, 2025

Mileage

79,000 mi

wont go into park

NHTSA ID

11683361

Incident

Jun 10, 2025

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while stopped at stop light, the vehicle shut off with the check engine warning light illuminated. Due to the failure, the vehicle was towed to a dealer and the transmission was repaired. Despite the repair, the vehicle continued to shut off without warning. One day while driving 60 MPH, the vehicle shut off without warning, and the contact was stranded in the middle of the highway. The vehicle failed to restart after several attempts even with assistance from the Highway Patrol. Due to the failure, the vehicle was towed to the residence and remained at the residence unrepaired. The manufacturer was not notified of the failure. The failure mileage was unknown.

NHTSA ID

11681574

Incident

Nov 1, 2022

I am unsure which component maybe failing, Vehicle has not been in altered in any way ,inspected yet, nor has any warning indicators. This 2021 Chevrolet Trailblazer uses a traditional key for ignition. On several occasions now, the key is becoming lodged/stuck in the ignition when attempting to shut down or turn off the engine and remove the key. Have made sure foot is on the brake, front steering tires are straight, Shifter is properly engaged in the park position, and even jiggled the key tumbler assembly. Have had to leave the stuck key in the ignition while grocery shopping, until returning home to ask my fiance for his help and assistance. When this problem happens it is not only an inconvenience, but leaving a key in the ignition to an unattended car, obviously is not good, and leaves opportunity for many not good possibilites to occur.

NHTSA ID

11676670

Incident

Jul 27, 2025

The vehicle keeps vibrating binding lurching jumping when driving going in reverse and turning the car in a circle I took it in they replaces they rear end and transfer case on it there was a lot of metal shavings in both no clue or explanation why got the vehicle back over a month later to the same problems as before took it back in they went for a test drive with us and verified its still happening and that day they shrugged shoulders they dont know why or what's happing they supposedly got ahold of trailblazer and they said this is normal for these vehicles and safe to drive .the vehicle dont sound or feel very safe at all I am reaching out for help with this the vehicle does this every time you drive it

NHTSA ID

11667632

Incident

Jun 18, 2025

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while attempting to remove the key from the ignition, the key remained stuck in the ignition cylinder. The contact had to turn off and restart the vehicle several times to be able to remove the key. The contact stated that the failure occurred intermittently. The vehicle was taken to the dealer who sprayed the ignition cylinder to clean the cylinder; however, the failure persisted. The vehicle was returned to the dealer who diagnosed that the shift lock mechanism failed to recognize that the vehicle was in park(P). The shifter assembly was replaced. The manufacturer was informed of the failure and opened a case. The manufacturer referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 20,000.

NHTSA ID

11665088

Incident

Dec 5, 2024

Mileage

20,000 mi

At 44 K miles, my car started giving me a message "Shift in to park" after I stopped my car and turned off the motor. I was unable to essentially shut my engine off and leave my vehicle. I called the GMC shop, where they diagnosed it as faulty wiring. It is not under warranty, therefore I will encure the cost which is not a normal item to go out on a vehicle. Also, our 22 Trailblazer is also giving us this same message.

NHTSA ID

11659124

Incident

Apr 14, 2025

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while attempting to park the vehicle, the contact noticed that the gear shifter was inoperable, and the vehicle would not shift into gear properly. There was no warning light illuminated. The vehicle was taken to the dealer, where it was diagnosed and determined that the gear shifter had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 40,000.

NHTSA ID

11657251

Incident

Apr 28, 2025

Mileage

40,000 mi

The contact owns a 2021 Chevrolet Trailblazer. The contact stated while parking the vehicle, the gear shifter was shifted into park, however the shift to park warning light illuminated. In addition, the vehicle failed to turn off. The contact made several attempts to shift to park, and the gear shifter failed to function as intended. The contact stated that after several attempts, the shift to park warning light turned off and the contact was able to park and turn off the vehicle. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The dealer was made aware of the failure. The vehicle was scheduled for a diagnostic testing within the next several days. The manufacturer was made aware of the failure but provided no assistance. The contact was advised to contact the NHTSA Hotline to report the failure. The failure mileage was approximately 31,000.

NHTSA ID

11652476

Incident

Mar 13, 2025

Mileage

31,000 mi

Engine power reduced came on after I was driving from a patient’s home. My car started driving very rough. I had to pull over because I was in danger of being hit from behind. I took my car to a mechanic and was diagnosed with the code DTC P2714. I looked online and there are a lot of people having this issue and being put in dangerous situations when we drive. Chevy knows about the issue and has not issued any recalls. Unfortunately for me my vehicle is past the limited warranty so now I have to save up money to get my transmission serviced. I’m never buying American again. I could’ve been really hurt when my engine cut off.

NHTSA ID

11645476

Incident

Feb 21, 2025

This vehicle has approximately 35,000 miles of driving time on the odometer. This car will not recognize that the shift lever has been place into the Park position. Doors will not lock when the car is turned off. If trying to seek refuge from an assailant, the car will only alarm but will not lock the doors for safety. Also, while storing items in the vehicle while at a metropolitan hospital (where I work) or a metropolitan grocery/fuel station, the vehicle will only alarm but will not lock under any circumstance. The car is responding as if the car is still in a movement gear position and will not recognize the shift position of Park. I have heard of many similar documented cases regarding this particular shift issue in relation to the 2021 Chevrolet Trail Blazer yet there has been no related recall related to this ever more prevalent repair need. some reports (not ours...) report the automobile transmission converting to park while in movement and while in a selected movement shift position. I do not want this to happen to me. My car (VIN # [XXX] ) is at the dealership for repair. The dealership informs us that the needed part(s) are currently under manufacture at a supplier and that there is no estimated date for the part(s) arrival or date to complete this repair. The car cannot be driven safely in a metropolitan area because in cannot be locked with the ignition off and the car just continues to alarm if walked away from. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11627293

Incident

Nov 20, 2024

Receiving "Shift to Park" alert when vehicle is already in Park.

NHTSA ID

11626516

Incident

Nov 5, 2024

The contact owns a 2021 Chevrolet Trail Blazer. The contact stated that after shifting to the park position the message "Shift to Park" was erroneously displayed and the vehicle would not shut off. The contact had to shift multiple times before the transmission switched to the park position and the engine was able to be shut off. The vehicle was taken to the local dealer who diagnosed that the shifter was faulty and needed to be replaced. The vehicle was not yet repaired. The manufacturer was also notified of the failure and confirmed that the part was on backorder. The failure mileage was 16,600.

NHTSA ID

11625533

Incident

Nov 10, 2024

Mileage

16,600 mi

The contact owns a 2021 Chevrolet Trailblazer. The contact stated that while the gear shifter was in the park(P), the message “Shift to Park” was displayed. The vehicle was taken to an independent mechanic, who determined that the gear shifter needed to be replaced. The mechanic informed the contact to use the parking brake while parking the vehicle. The contact called the local dealer and was informed that parts were on back order. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The approximate failure mileage was 16,000.

NHTSA ID

11624902

Incident

Sep 1, 2024

Mileage

16,000 mi