Home · 2018 Cadillac Ct6-v · Complaints

What 10 owners told NHTSA about the 2018 Cadillac Ct6-v

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (10)Engine (4)Steering (3)Transmission & drivetrain (3)Body & structure (1)Brakes (1)Driver assistance (1)Electrical system (1)Electronic Stability Control (esc) (1)Fuel system (1)Lane Departure (1)

Newest first · 10 complaints

Jun 23, 2026Engine

Stuck Thermostat. Vehicle not achieving operating temperature in the correct time. ALL 3 of the people I know with CT-6's had the exact same issue this year.

NHTSA ODI 11745961

Dec 26, 2025Transmission & 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.

NHTSA ODI 11707182

Feb 15, 2024SteeringSuspensionBody & structure

Yes my car was sold to me with structural damages, and I was told any of this when I purchased it!!!!

NHTSA ODI 11572148

Feb 21, 2023BrakesEngine

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.

NHTSA ODI 11508253

Feb 21, 2023Lights

MY DRIVER FRONT HEAD LIGHT IS PARTLY NOT WORKING. I BELEIVE IT IS AN LED LIGHT AND THE FACT THAT IT NO LONGER WORKS IS NOT WHAT I EXPECTED FROM LED, IT SHOULD LAST MUCH MUCH LONGER THAN 5 YEARS; AFTER ALL IT IS A CADILLAC AND IT SHOULDN'T HAVE HAPPENED. I REQUESTED CADILLAC CORPORATE TO ASSIST ME WITH THIS AND ALL THEY WOULD DO FOR ME IS GIVE ME A $250.00 CREDIT TOWARDS THE REPAIR THAT IS APROX. $1,800.00 THIS HEAD LIGHT IS DEFECTIVE AND THEY SHOULD DO GOOD BY ME, THIS IS MY 5TH. CAR WITH THEM. THANK YOU FOR YOUR HELP [XXX] INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

NHTSA ODI 11508275

Mar 3, 2021SteeringDriver assistanceLane Departure

ON MAR 1, 2021 WHILE DRIVING SUPER CRUISE MODE, MY CAR JERKED VIOLENTLY TO THE LEFT ALMOST STRIKING ANOTHER CAR. I WAS ON THE FL TURNPIKE ABOUT 20 MILES NORTH OF ORLANDO HEADING SOUTH. THE HIGHWAY WAS INCREASING FROM 2 LANE TO 3 LANE SOUTHBOUND AND I WAS IN THE RIGHT LANE. WHEN I ENTERED THE LANE TRANSITION, THE CAR DRIFTED RIGHT . AS THE CAR CAME UPON THE NEW WHITE LINE THE CAR ABOUT CENTERED IT. THE CAR TURNED HARD LEFT, AND TURNED OFF SUPER CRUISE. FORTUNATELY, I WAS ABLE TO GRAB THE STEERING WHEEL AND CORRECT THE TURN. WE DID NOT CRASH, BUT IT WAS MOST UNSETTLING.

NHTSA ODI 11398939

Jan 21, 2021Transmission & drivetrainEngineFuel system

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. I WAS TOLD BY BOTH CADILLAC DEALERS THAT THEY WOULD NOT HELP BECAUSE THEY NEEDED TO 'DIAGNOSE' THE CAR AND COULDN'T UNTIL FIVE DAYS LATER. I WAS OFFERED AN UBER RIDE IN A CITY THAT HAD 0 ZERO UBER, TAXI OR LIFT SERVICES. I WAS HUNG UP ON BY THESE PEOPLE, THEY WERE RUDE AND THIS WAS ON CHRISTMAS EVE. I HAD TO WALK TO A CAR RENTAL COMPANY AND PAY OVER $400 DOLLARS SO I COULD SPEND CHRISTMAS WITH MY FAMILY.

NHTSA ODI 11389316

Oct 16, 2020SteeringElectronic Stability Control (esc)Engine

MY ENGINE LIGHT IS ON AND THIS IS THE 15TH TIME I HAVE BOUGHT MY CAR IN FOR VARIOUS ENGINE PROBLEMS LIKE ENGINE POWER REDUCED AND OTHER PROBLEMS WITH THIS CAR. THE CAR WOULD JUST STOP IN THE MIDDLE OF THE RIDE OR JERKING AS I DRIVE IT. I HAVE BEEN ON THE HIGHWAY WHEN IT HAS STALLED BEFORE AS I DRIVE. I HAVE HAD THESE PROBLEMS SINCE I PURCHASED THE CAR IN 2018

NHTSA ODI 11364614

Jul 24, 2020Transmission & drivetrain

LOSS OF ALL VEHICLE POWER WHILE TRAVELING ON THE FREEWAY AT HIGHWAY SPEEDS. VEHICLE CHECK ENGINE, POWER LIMITED, AND ELECTRIC MOTOR OVERHEAT WARNING LIGHTS COME ON. THE COMBUSTION ENGINE WILL NOT START, AND BATTERY POWER AVAILABILITY GOES TO ZERO. THIS IS VERY DANGEROUS TO PUBLIC HEALTH AND SAFETY DUE TO INSTANTANEOUS LOSS OF COMBUSTION ENGINE AND ELECTRIC BATTERY POWER WHILE IN FAST-MOVING HIGHWAY TRAFFIC. THERE ARE SEVERAL INSTANCES OF THIS SAME PROBLEM OCCURRING IN MANY CADILLAC OWNERS FORUMS, SO GENERAL MOTORS KNOWS THERE IS A PROBLEM WITH THEIR CT6 PHEV TRANSMISSIONS. THE FIX SEEMS TO BE REPLACING THE TRANSMISSION DUE TO A BAD CLUTCH PACK, BUT PEOPLE COULD GET HURT IF THIS ISSUE IS ALLOWED TO CONTINUE WITHOUT A PERMANENT SOLUTION.

NHTSA ODI 11341298

May 30, 2018Electrical system

RIGHT AFTER PURCHASE, THE NAV SCREEN KEPT FLICKERING, CAUSING A DISTRACTED DRIVER SITUATION AND A HAZARD. THE DEALER DID EVERYTHING THEY COULD PER GM GUIDELINES, BUT EVEN AFTER THE 1ST SERVICE VISIT, THE CAR WOULD SHUT DOWN IN DRIVE MODE, AS THE VEHICLE WAS IN MOTION. THEN THE VEHICLE WOULD NOT SHUT OFF USING THE POWER OFF BUTTON. GM IS TELLING THE DEALER, THE NAV FLICKERING SCREEN IS NOT A SAFETY HAZARD, HOWEVER I BEG TO DIFFER IF EVERY 2 MINS, A DRIVER IS FIXATED, FOCUSED ON THE SCREEN MORE SO THAN ON THE ROAD, WHICH HAS CAUSED ME TO RUN OFF THE ROAD A FEW TIMES. THIS IS A SERIOUS SAFETY HAZARD AND ELECTRICAL CONCERN THAT GM DOES NOT SEEM TO CARE ABOUT EVEN AFTER 60+ DAYS AT THE DEALERSHIP.

NHTSA ODI 11098735

Working with the data? Download all 10 complaints as CSV · fetched from NHTSA July 21, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2018 Cadillac Ct6-v verdict →