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 Chevrolet Trailblazer EXT owners, lightly cleaned up (personal details are redacted by NHTSA).
My key will not come out of the ignition I had to unscrew and remove the bottom of my steering to push the button also all of my instrument gauge do not work including the speedometer and all gauges so I never know my temperature or fuel level, oil pressure they all are not working properly my speedometer only works sometimes. Also my engine is runny rough and I hear a vibration and ticking. My check engine light is and I'm getting code saying theres a leak in the fuel EVAP system. I have searched the internet and everyone has the same problems with their 2003 trailblazers. Why isn't Chevrolet recalling these problems its fustrating they want several hundreds of dollars I cannot afford
I purchased a 2003 Trailblazer from an individual. The front differential had a hole in it. So I purchased a differential from a scrap yard. 90 day warranty. Still had a noise . I still had a noise front differential was out again. I purchased the third differential from a different yard took it apart . Found the driver side bearing bad. It seems to be a very common problem because the driver side drivers constant. I was wondering if there is a recall. I see a lot of complaints online. Thank you there was a fire the differential grease burnt bearing went out and chard motor and surrounding area no real damage.
While putting the vehicle in 4-wheel drive it began to accelerate. Vehicle ran into a guard rail and rolled down into a ditch. Owner contacted the dealer, who said it was the fault of the driver. Later, dealer contacted the owner, and informed him that the 4-wheel drive key was broken.
Driving down road on the way to hospital and Trailblazer made a loud clunk. Then started making a whirring noise. Finished driving slowly to hospital as not to mess anything else up. Pulled in and parked. Got ready to leave hospital and had no reverse only foward.
2003 Chevrolet Trailblazer - purchased in May of 2003 off of the sales floor - around 5 miles on it - truck began squeaking - took it in, they said bad break pads, changed them out and gave it back (2 days without truck) - squeaking still there - took it back in - service tech said the front spindle was bent - told me I couldn't drive it it was unsafe (5 more days without truck) - at the same time they take truck to body shop because rear hatch won't shut it too is bent - same with the hood (hmmmmmmmm!!!!) - rear wiper motor then busts (now I'm erked) - driving down the highway at 55 and truck shuts off - no power steering almost wreck it seems the gas gauge is not accurate!!!!!!! - then blower motor won't shut off without taking fuse out ... …
Dt: left driver's side outside mirror is not holding the correct settings, and clicks constantly. The mirror is hitting against something, and turns completely to the ground. When using keyless entry the mirrors also turn to the ground. The mirror is changing by itself, and it is not going back to the correct setting. The mirror is always making a clicking noise and it is facing downward. There is no problem with the right side. The dealer replaced the right side mirror, and from then on the left side has not worked. Consumer has taken vehicle to dealership 4 or 5 times to be checked. Dealership insists the mirror is working fine. But as soon as the consumer leaves the dealership the mirror will work for a couple of hours and then stop working properly. …
I own a 2003 Chevy Trailblazer lt @ 35,825 miles I reported my vehicle binds up on turns & of course the garage found nothing (drove it 20 miles for comparison @ the time). So now that I am up to 82,090 miles now I mention suspension issues still & of course they find both lower ball joints need replaced @ $320.06 & left outer tie rod end broken @ $170.80. Also they inform me I need to replace 3 of my 4 stabilizer bar links are loose & rattling @ an estimate of $320.00 (haven't done yet) also, I have looked on a website called mycarstats.com & found many others with these same issues with this vehicle @ much lower mileage & where tie rod issue caused an accident -- they weren't as lucky as me. Also people I work with who have this same yr & model vehicle have had to have ball joints, sway bars replaced, and other suspension work @ lower mileages. …
My 2003 Chevy Trailblazer has a third brake light across the top hatch .while driving down a busy highway it was flying like a wing on the back of my vehicle luckily dot falling completely off but when I stopped it came crashing down onto my window of hatch luckily not breaking all I could do is break it completely off so it would not fly into someone's windshield behind me I work with a lady with the same make and model and hers flew right off her latch causing it to smash luckily no one was behind her. I also have it in the shop due to rusty corroded hoses that went to transmission causing all fluid to drain almost burning up my transmission no indication lights ever came on other than it skipping a little luckily a service engine light came on a week later I took it to garage and just in time. …
The transmission cooling lines corroded which caused the transmission fluid to leak out while on a 20 mile round trip from our house. The truck started to run rough as we pulled in the driveway and there it died. I had it towed to a local transmission repair shop where they confirmed the transmission was dead, rebuild or replace. I paid to tow it to the GM dealership where I bought the truck and they confirmed the tranny was dead. Aluminum cooling lines rotted out, drained the fluid and the unit fried. There are no warning lights or monitoring of this fluid level per GM. This truck had been serviced by this dealership. The service mechanic told me that this is not a common occurrence but this is not rare either. He said GM will not help with the repairs and he was right. I had the local tranney shop do the repairs for 2500.00, less than GM's 4500.00. …
The incident occurred while driving home after dropping my son off at work on I-95. I was traveling between 65 and 70 MPH and passing a semi when my vehicle suddenly and with no prior warning shifted into second gear. Luckily I was able to maintain control of my car and able to drive it the rest of the way home. On Monday I drove my vehicle as instructed to the mj sullivans, the dealership in which I bought the Trailblazer, for service. I was then notified that the stator support bushings in the transmission failed and that it would actually be cheaper to replace the transmission. Interestingly, the new transmission comes with a 10yr/100K mile warranty and my vehicle has only 69000 miles of highway miles. Asked the service engineer about how unusual this type of failure is and they told me highly considering the wear on other parts in the transmission. …
Transmission complaints in other Trailblazer EXT years
Frequently asked questions
How common are transmission problems on the 2003 Chevrolet Trailblazer EXT?
NHTSA has 49 complaints about the transmission & drivetrain of the 2003 Chevrolet Trailblazer EXT, 16% of the model year's 313 complaints. The component named most often is automatic transmission (29 mentions).
Is there a recall for 2003 Chevrolet Trailblazer EXT transmission problems?
No. NHTSA lists no transmission & drivetrain recall for the 2003 Chevrolet Trailblazer EXT, though it has 3 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 Chevrolet Trailblazer EXT transmission problems start?
Half of the complaints with a recorded mileage happened before about 61,000 miles, and 9% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 1 fire 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.