Which parts fail
Components named in complaints (automatic and manual transmissions, CVT, axles, driveshaft, 4WD/AWD).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2003 Cadillac CTS owners, lightly cleaned up (personal details are redacted by NHTSA).
Tl* the contact owns a 2003 Cadillac CTS. The contact stated that the transmission assembly made an abnormal sound and the gears slipped without warning. Martin Buick GMC (12101 w olympic blvd, los angeles, ca 90064, [phone]) was unable to provide a permanent remedy; therefore, the failure continued. The vehicle was not repaired after several extensive repairs from the dealer. The contact was provided with a loaner vehicle for more than three months. The dealer returned the vehicle to the contact without it being repaired. The vehicle was unable to be driven safely. The manufacturer was notified of the failure and the case manager was to follow-up with the dealer and owner to determine if there were guidelines for a repair. The VIN was not available. The approximate failure mileage was 59,000.
The pcv valve system design is defective. On (4) occasions the pressure build-up causing massive oil leaks at the valve cover. I experienced smoke from the engine compartment as oil leaked onto a hot engine. A potential engine fire. It took years for the Cadillac dealers to correct the problem. This is a extreme cold weather issue. The automobile was in arizona for a few years and the issue was not a problem but once returned to michigan, the problem got serious. I have all of my repair documents. This car should has been recalled. It is not safe to drive. I was lucky as I was near dealers when this occurred.
Tl* the contact owns a 2003 Cadillac CTS. While driving 30 MPH, the vehicle jerked without warning. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The VIN was not available. The approximate failure mileage was 65,000. Updated 2/24/15 updated 9/15/2017
Noticed a high-pitched whine coming from rear at 50000 miles. Stopped by the dealership, the service manager drove the vehicle and stated it was the tires causing the noise. Continued to drive the vehicle, sound became more pronounced. A check engine light appeared, so needed to service the car. This repair was unrelated to the whine, an emission control valve had failed. While at the dealership requested they check, again, the whine from the rear. Was notified that indeed it was the differential that needed replacing. Have not taken possession of the vehicle, but am concerned about driving it now. Much concerned about the reliability of the vehicle.
We own a 2003 CTS Cadillac with 40,000 miles and still under warranty. I have had the car in for repair several times for the same reason. The car shakes at certain speeds. Eg. 47, 59,65,69, and 75 miles per hour. The wheel actually shakes in my hands. It is a problem with the transmission. Cadillac stated it was characteristic of the 2003 CTS. Maybe an escort but not a Cadillac. They offered to extend the warranty on the transmission to 100,000 miles. Whoopie. I now must drive a car that I feel is dangerous to drive. I really believe the transmission will totally fail and soon. It gets worse and worse. Thanks for viewing this letter.
Tl* the contact owns a 2003 Cadillac CTS. The contact stated that while driving 60 MPH, the engine low power warning light illuminated as the engine stalled. The contact was able to restart the vehicle, but the engine loss power warning light remained illuminated. The vehicle was taken to the dealer, who replaced the throttle body assembly. The vehicle was repaired. In addition, the contact stated that four years after the repair the vehicle would not start at the first attempt. The manufacturer was not notified of the failure. The approximate failure mileage was 72,579. Updated 8/12/14 updated 08/20/2014
There needs to be an in-depth investigation regarding the number of CTS and CTS-v rear differentials that have been replaced. I have now been through 2 personally, and an online poll of 65 CTS-v owners showed this: 26% have had 1 replacement, 5% have had 2 or more replaced, and 8% have had 3 or more replaced. The link for this poll is: http://cadillacforums.com/forums/showthread.php?p=305662&posted=1#post305662. Please contact me regarding any information learned. Thank you.!
Dt: vehicle lost power when the consumer hit the brakes. The transmission jolts and then the engine shuts off. It has been to the dealer 6 times since January. The dealer tried something different every time she took it in. Manufacturer said she could have a new vehicle if she paid for it. She wanted to get rid of the vehicle. The check engine light illuminated.
The differential in my 03 Cadillac CTS developed a serious leak. The defect required (3) trips to the dealer to repair. The last repair, (appears to be the right one) was the replacement of the differential. This type of defect can lead to loss of differential fluid resulting in failure of the unit and possible accident. I have found this leak on several other "03" CTS.
I am and have been experiencing numerous failures with my vehicle. I have contacted GM numerous times beginning approximately a few months after I purchased the vehicle to inform them that the vehicle is defective, only to be told my vehicle is out of warranty, so they refuse to fix it or give my one that is not defective. My vehicle is still defective to this date.
Transmission complaints in other CTS years
Frequently asked questions
How common are transmission problems on the 2003 Cadillac CTS?
NHTSA has 25 complaints about the transmission & drivetrain of the 2003 Cadillac CTS, 8% of the model year's 313 complaints. The component named most often is driveline › differential unit (7 mentions).
Is there a recall for 2003 Cadillac CTS transmission problems?
No. NHTSA lists no transmission & drivetrain recall for the 2003 Cadillac CTS, though it has 4 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2003 Cadillac CTS transmission problems start?
Half of the complaints with a recorded mileage happened before about 30,000 miles, and 39% before 25,000 miles.
Is it dangerous?
Owners linked 2 crashes, 0 fires and 0 injuries to transmission & drivetrain problems on this model year. If you notice symptoms, have the car checked before driving further.
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.