Certain 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, the Malfunction Indicator Lamp (Check Engine Light) will illuminate and a diagnostic trouble code will set. Additionally in some cases, the engine cooling fans may run after the engine is switched off. This special coverage covers the condition described above for a period of 15 years or 150,000 miles (240,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership. For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or
full bulletin at NHTSA ↗2021 Cadillac XT6 engine problems
moderate Owners of the 2021 Cadillac XT6 have filed 3 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of October 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
3
Recalls
0
Avg fix
$3,100
When does it fail?
Of the 3 engine complaints filed for the 2021 Cadillac XT6, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
full bulletin at NHTSA ↗The 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 customer that it is normal for the delay.
full bulletin at NHTSA ↗This 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 other states.
full bulletin at NHTSA ↗This service bulletin provides diagnostic repair information to correct an oil leak in the engine.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 3 most recent
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.…
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…
The contact owns a 2021 Cadillac XT6. The contact stated that while sitting inside the vehicle, the vehicle felt unbalanced. Upon inspection, the contact noticed that the H-pipe was leaning more to the right side. The H-pipe was not centered as intended. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. The contact stated that in the past, while the…
Had engine trouble with your 2021 Cadillac XT6?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2021 Cadillac XT6?
It's a documented issue but not catastrophic. 3 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Based on the 3 complaints filed, engine issues most often appear around 37,000 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2021/Cadillac/XT6.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.