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 Chevrolet Silverado 2500 owners, lightly cleaned up (personal details are redacted by NHTSA).
In the middle of the taxiway, while I was traveling my truck turned off while it was running and did not turn on again, putting my safety at risk by being in the middle of the taxiway, after several minutes the truck was able to be removed from the road, then I was able to investigate that I am not the only one that the same thing has happened to him, there is no Safety Recall in this regard, the GM fabric is aware of these cases but only wrote a TSB, it was diagnosed with the scanner and it gave code U1800, before the event there were no lights warning but after the event there is a check engine light on.
Tl* the contact owned a 2003 Chevrolet Silverado 2500. While driving 25 MPH, the contact made a left turn and the reduced engine power light illuminated. The steering failed and the vehicle crashed into a tree. The air bags did not deploy. The vehicle was destroyed. The contact suffered nerve pain in the back and legs from the impact of the crash. Medical attention was not received. A police report was filed and the vehicle was towed. The manufacturer was not made aware of the failure. The failure mileage was 196,000.
Tl* the contact owns a 2003 Chevrolet Silverado 2500. While driving 40 MPH, the reduced engine power light illuminated on the instrument panel. The vehicle stalled in the middle of the highway, but the contact was able to pull over to the side of the road. The vehicle was taken to an independent mechanic where it was diagnosed, but not repaired. The manufacturer was notified of the failure. The failure mileage was 195,000.
The exhaust manifold bolts are breaking creating a fire hazard from the hot exhaust reaching the wiring harness, it is also creating fumes in my cab. First noted a noise a week ago, found it to be a exhaust leak and the leak has gradually gotten worse. I am unable to not drive to the truck due to work.
The vehicle goes into reduced engine power while driving. The engine loses power to about 20 MPH. If driving 70 MPH it is very dangerous because the sudden reduced engine power will cause a severe accident and possibly kill somebody. This has been happening the last few months.
The exhaust manifold bolts are breaking on the 6.0 engine. I think GM should do this repair since I have talked to several people and this is very common. It is a design defect as far as I am concerned. I have put up with this as it started as a small leak but is getting worse.
We were traveling east on I-90 in mass. Traffic came to a sudden stop. When the brakes were applied the truck began to slow and then the brake pedal went to the floor. Upon investigation after the crash we found at least two badly corroded brake lines that had burst.
My 2003 Silverado pickup truck has been found to have a common and recurrent problem. Exhaust manifold bolts break, and on the driver side rear, they can be expensive to repair. A few minutes of web searching on this topic produced a number of results and my conclusion is the issue is common. The online complaints also indicate that the success rate for the repair is not good, with many repaired vehicles having subsequent bolt failures. My vehicle is in an authorized Chevy service garage having the bolts replaced. The original estimate was for $486, if cylinder head did not need to be removed. The service technician broke a tap off in the rear most bolt location. I don't know if it happened before head removal or after. It became necessary to remove the cylinder head and was requoted at $1600. A call was made to GM 3-6-12. …
This is the 3rd time for injectors in our 2003 injectors, not one injector...all 8. Lucky this time just 4 hrs. From home and somebody to come with trailer to pick us up. Seems injectors only last 20 tp 30,000 miles and they are gone cracked. GM wont back them knowing they are a problem, and $5,000.00 each time they are replaced. GM injectors are junk out the door and leaving hundreds of owners stranded on highway and suffering tow bill and repairs, but this time we almost got rear ended by a semi truck which slammed on his breaks blowing a tire to miss us and our horse trailer with 3 horses in it. …
Consumer complaint concerning transmission failures on 2003 Silverado. The transmission fluid was burnt, the reverse gear was inoperable and the transmission shifter was loose. The power steering fluid was low. Fluid was leaking from the gear box. The front seal on the power steering pump was worn and leaking, as well as the lower hose. The water pump gasket and lower radiator hose was leaking. The battery was replaced because it would not hold a charge. The A/C would only blow out air from the defrost vents. The A/C heater mode door actuator was worn. The check engine light illuminated. The fuel filter was replaced. The panel on the drivers seat was warped. The tires were replaced, however months later one of the tires developed a slow leak, due to a pin hole located in the sidewall. The rear pads and rotors were replaced. The front and rear shocks were replaced. …
Engine complaints in other Silverado 2500 years
Frequently asked questions
How common are engine problems on the 2003 Chevrolet Silverado 2500?
NHTSA has 31 complaints about the engine & cooling of the 2003 Chevrolet Silverado 2500, 7% of the model year's 449 complaints. The component named most often is exhaust system (2 mentions).
Is there a recall for 2003 Chevrolet Silverado 2500 engine problems?
No. NHTSA lists no engine & cooling recall for the 2003 Chevrolet Silverado 2500. 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 Silverado 2500 engine problems start?
Half of the complaints with a recorded mileage happened before about 107,000 miles, and 7% before 25,000 miles.
Is it dangerous?
Owners linked 2 crashes, 2 fires and 1 injury 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.