Most common 2018 Cadillac CT6 problems
Share of the 9 complaints; one complaint can involve more than one system. "~" is the median mileage when the problem started.
Cadillac CT6 complaints by model year
Best CT6 years: 2018. Years to avoid: 2019. Compare all years →
What 2018 Cadillac CT6 owners say
Engine & cooling
The brake makes a rattling and metal grinding sound, the dealership said nothing is wrong with the brakes, still problematic. The transmission shifts too hard. Dealer said nothing wrong. Yet cat kicks too hard.
My Cadillac CT6 (2018) quit working while on the expressway. I was in the middle of no where, in georgia. This made for a very dangerous situation as the car suddenly lost all power going to the wheels while driving at approx. 75 MPH. I was barely able to get around traffic to be able to pull over as there was 0 power. When the tow truck from Cadillac arrived we were told we were not allowed to ride in the truck because of covid. We were made sit in the rain in 40 degree weather while I spoke with my home Cadillac dealer as well as the nearest to where I was. Both dealers were extremely unhelpful, my car is still under factory warranty and was just in for transmission work about a week prior (I've taken the car in three times for transmission issues and it still has something wrong with it. …
Transmission & drivetrain
Front differential case ripped in half and separated from the ring gear. The broken chunk of differential case and pinion was still attached to the driveshaft while coming to an abrupt stop. Damage done within driveshaft tunnel. No warning, no vibration, no cause for concern, just catastrophic failure. Differential and propeller shaft were replaced by an independent mechanic. Cadillac has not been notified as of today, receipt for repair available upon request.
When vehicle was purchased new there was a slight bearing wear noise at the front driver side, which grew louder with years. Noise synchronized with tire rolling rpm. Replacing (my self) front trans axle, the brake pads, shaving rotors, & wheel hub bearing did not fix noise. Next; Dealer shop reported that the AWD front transfer case (differential) had a bad bearing AND that this was a common problem with the model car. $1600 repair bill.
2018 Cadillac CT6 engines & fuel economy
| Engine | Transmission | Drive | MPG city / hwy / combined |
|---|---|---|---|
| 2.0L 4-cyl turbo | 8-speed automatic | RWD | 22 / 30 / 25 |
| 2.0L 4-cyl turbo plug-in hybrid | CVT | RWD | 23 / 29 / 25 |
| 3.0L 6-cyl turbo | 8-speed automatic | AWD | 18 / 26 / 21 |
| 3.6L 6-cyl | 8-speed automatic | AWD | 18 / 27 / 21 |
EPA ratings. Class: Large car.
Frequently asked questions
Is the 2018 Cadillac CT6 a good car?
Based on 9 owner complaints filed with NHTSA, the 2018 CT6 rates average: 28% fewer complaints than a typical year of the CT6 at the same age. It is one of the best CT6 years by this measure. Complaint counts don't account for sales volume or individual maintenance, so have any used car inspected before buying.
What is the most common problem with the 2018 Cadillac CT6?
The engine & cooling — 3 complaints, 33% of all complaints for this model year. Next are the transmission & drivetrain (3) and fuel & propulsion system (2).
How many recalls does the 2018 Cadillac CT6 have?
NHTSA lists no recalls for the 2018 Cadillac CT6. You can still confirm with your VIN using our VIN recall check.
What are the best and worst years of the Cadillac CT6?
The best years by complaints, compared at the same age, are 2018. Years to avoid or approach with caution: 2019. See the full Cadillac CT6 years comparison.
At what mileage do 2018 Cadillac CT6 problems happen?
The median mileage reported in complaints is about 36,000 miles; 100% of problems with a recorded mileage started before 50,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.