Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2003 GMC Yukon owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2003 GMC Yukon. The contact stated that upon purchasing the vehicle from a towing company, the vehicle would not start. The battery was instantly replaced. The contact stated that the vehicle would wobble and shut off inadvertently while driving. The vehicle was taken to an independent mechanic where the stabilizers and shocks were replaced. The independent mechanic then took the vehicle to an electrical failure specialist where it was diagnosed that the front end of the vehicle was experiencing electrical failures. Additionally, the contact stated that a warning message stating that the air bags were not working was displayed. The dealer and the manufacturer were not notified of the failure. The vehicle was not repaired. The failure mileage was approximately 150,000. Consumer stated in 2016 the odometer was at 175,000 miles per car fax. …
Tl* the contact owns a 2003 GMC Yukon. The contact stated that the battery drained prematurely. The contact replaced the battery several times and the alternator was also replaced; however, the failure was not corrected. The vehicle was taken to an independent mechanic for inspection who located the failure at the engine electrical wires. The vehicle was not repaired. The manufacturer stated that the VIN was not included in the manufacturer battery drain replacement recall 02066. The approximate failure mileage was 90,000.
Tl* the contact owns a 2003 GMC Yukon. While driving approximately 50 MPH, the vehicle experienced independent deceleration and the reduced engine power warning indicator illuminated. The vehicle was previously taken to an independent mechanic who diagnosed that the fuel pump, spark plugs, transmission, and alternator needed to be replaced. The vehicle was repaired, but the failure recurred. The manufacturer was notified and transferred the contact to NHTSA. The failure mileage was approximately 100,000.
I have a 2003 Yukon denali I purchased and it has given me the reduced engine power light and almost had a few accidents on the highway because it drops the speed to 20 MPH also it has the check engine codes as p0120 and p2135 I have been aware that GM has not found a solution to this and wanted to see if there is any recalls as I am very afraid of being in a very serious accident with my children in the car. The consumer stated the vehicle was repaired and requested withdraw the complaint.
Car looses power and goes into reduced engine power. Unable to drive over 2mph. Happens at random times, in all modes of travel, uphill, downhill, from a stop and acceleration. The worst was when it happened going 55mph on a highway. Two separate mechanics have been unable to pinpoint the problem even after $1,300 worth of work and new parts. It's been happening since mid October 2019
Found a broken off exhaust manifold bolt on driveway 3 years ago. Found another broken one today. Both are from the same side. Now instead of 6 bolts I have 4 bolts. This is causing an exhaust leak, engine light and emissions problems that harm the environment. This is an ongoing problem per this article: https://www.youtube.com/watch?v=0yg6wlbnzgi.
My 03 Yukon Denali is experiencing all of the same things that the recall on the 2021 Yukon is experiencing. What do I do? The recall notice I am referring to is N252494000
I have had multiple ongoing electrical issues with this vehicle. Starting in 2005, the exterior electronics (I.e. Signal lights, stop lights, head lights, etc) began to malfunction. For example, I would trigger the signal for one direction and all of the signals for all directions would trigger... Even pressing the brakes triggered all of the exterior signals. The dealer had a hard time isolating my problem, but after several visits, the dealer was finally able to diagnose and rectify it... They isolated it to a junction box where all of the electronics terminate. However, by this time, my vehicle was out of warranty, so I had to cover the costs for repairing the problem myself. My most recent issues, which, by the way, seem to be common issues, are triggered by a message stating, "reduced engine power". This particular issue does not always render the same results... …
Engine ticking on startup, lasts for 5 minutes currently - longer on cold starts or after letting the car sit overnight. Progressively has gotten louder and longer in duration since reporting the failure last year to the dealership. This piston "slap" noise described appears to be manufacturer defect in 5.3 liter engine where shipment of engines with cylinder heads that are oversized or pistons shipping as undersized is causing warping on piston head, hence the reason why the noise progressivly gets louder and longer lasting as time progresses. Original dealership has documented the report of the noise with no result or attempt to fix. Customer has purchased extended warranty prior to the evidence of this failure, at time of purchase. …
December 2008- instrument cluster went out- speedometer no longer working December 2008- battery gauge no longer working March 2009- stabilitrak issues...sometimes the stabilitrak would work and at times it would not work July 2009 to January 2010- reduced engine power (almost cause 2 wrecks) could not perform a diagnosis...could not read computer. Changed fuel pump. No more reduced engine power message August 2011- wheel bearing issues. Reduced engine power (almost caused wreck...backed up traffic) September 2011- gas pedal sticking November 2011- reduced engine power...happens 5 times within a 30 mile trip. Attempted to resolve problem several times, but running out of options. Have to kill car in middle of highway or intersection to get car to work properly.
Engine complaints in other Yukon years
Frequently asked questions
How common are engine problems on the 2003 GMC Yukon?
NHTSA has 36 complaints about the engine & cooling of the 2003 GMC Yukon, 13% of the model year's 276 complaints. The component named most often is engine (6 mentions).
Is there a recall for 2003 GMC Yukon engine problems?
No. NHTSA lists no engine & cooling recall for the 2003 GMC Yukon, 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 GMC Yukon engine problems start?
Half of the complaints with a recorded mileage happened before about 120,000 miles, and 7% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 0 fires and 0 injuries to engine & cooling 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.