2021 Cadillac XT6 Engine Problems
- Complaints
- 5about this part
- Share
- 24%of 21 total for the year
- Median mileage
- —not reported
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 5 complaints about the engine of the 2021 Cadillac XT6, 24% of the 21 complaints for this model year.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“I noticed a water sloshing sound behind the dash when first starting out for about a month. I didn’t get any warning lights or notice anything leaking under the car but when I checked under the hood the coolant reservoir was empty. I made appointment at GM dealership and they found I had a leak along the side seam of my radiator. The car only has 61k miles! I found online that GM has noted a structural design issue in my XT6. The radiators were engineered with tight thermal break tabs. …”
NHTSA complaint #11772504, filed 2026-10“1)The display on dash reads upon start up, “Steering Assist Reduced”. 2)There is no Engine temperature readout displayed on cluster. 3)When the vehicle is turned off, the coolant fan stays running for a few minutes at full speed. All of these issues are correlated. Also, many XT5’s & XT6’s have had this issue in the past.”
NHTSA complaint #11639372, filed 2025-01“Car started and ran at idle for 5 minutes. 10 minutes later when attempting to restart, the engine churned for several seconds then ran for about 2 seconds and cut out. Press to Start button remained showing green and would not respond to being pressed. The car was stationary in my garage; this would have been extremely dangerous if it happened on the highway. It seems to be a complete failure of the fuel system on a 2021 model with under 27,000 miles”
NHTSA complaint #11617101, filed 2024-09“The vehicle's check engine light came on late afternoon and then started with a delayed turn over, but not actually starting thr following day. The vehicle had to be towed to the dealership. The technician and service advisor commented immediately that it is likely the fuel pump control module. With the commentary about the likely cause was that this is a widespread issue among GM vehicles. Thankfully, the vehicle was at home when it stopped starting but the transition from check engine to stopping operation was almost immediate.”
NHTSA complaint #11559826, filed 2023-12Related service bulletins
- 11024390Oct 21, 2025Certain vehicles listed above, may have a condition that could cause the engine coolant thermostat to open at a lower temperature than intended. If this condition were to occur…
- 11026017Jun 5, 2025This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
- 11024485May 15, 2025The service bulletin advises the tech of a normal transmission shift condition and the delay in throttle response when the throttle plate is opened rapidly and advises the…
- 11020254May 7, 2025This service bulletin provides information to dealership personnel for new vehicles with less than 1,000 miles that may not pass California smog inspection or smog inspection in…
- 11019547Apr 22, 2025This service bulletin provides a procedure to test and replace the battery distribution fuse block if found the cause of the DTC and electric coolant pump inoperative.
- 11019543Apr 22, 2025This service bulletin provides diagnostic repair information to correct an oil leak in the engine.
- 11019503Apr 18, 2025This warranty administration bulletin provides policy information on vehicles outside of a California Emissions State who move to and register their vehicle in a California…
- 11019378Apr 12, 2025This service bulletin provides a procedure to replace the FPDCM if found to cause customers concerns of Crank No Start, Stalling, Malfunction Indicator Lamp (MIL) Illuminated…
- 11017508Apr 3, 2025This service bulletin provides a procedure to add deadener to the batter tray bracket to correct customer concerns of a Service Engine Soon (SES), Reduced Power, Service Brake…
- 11017443Apr 2, 2025This service bulletin provides a repair procedure to correct a customer concern of a Malfunction Indicator Lamp (MIL) Illuminated - DTC P3055 Set.
Engine: other model years
Other parts of the 2021 Cadillac XT6
5 complaintsBack-over prevention (rear camera)
4 complaintsFuel system
4 complaintsOther or unknown
3 complaintsSteering
3 complaintsForward collision avoidance
2 complaintsBrakes
1 complaintsEngine cooling
1 complaintsTransmission and drivetrain
1 complaints
← All problems reported for the 2021 Cadillac XT6
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology