2003 Chevrolet Trailblazer EXT 370 Engine Problems
- Complaints
- 1about this part
- Share
- 7%of 14 total for the year
- Median mileage
- 109,654miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 1 complaints about the engine of the 2003 Chevrolet Trailblazer EXT 370, 7% of the 14 complaints for this model year. Where a mileage was given, the median is 109,654 miles.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“Vehicle started leaving spots of oil on the ground over night. Was driving to work on wednesday and a bluish cloud of smoke was trailing behind me. Arrived at work and let truck cool down after which I crawled underneath and with a mirror was able to locate the leaking rear main seal. This is a common problem with GM,s 5.3 liter engines. Multiple forums are posting many people complaining of the same issue. Gm needs to stand behind there products and repair this issue which again is a wide spread known problem.”
NHTSA complaint #10703557, filed 2015-04, 109,654 milesRelated service bulletins
- 11004761Jun 28, 2024This service bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or…
- 10211658May 2, 2022This service bulletin provides policy information on warranty administration guidelines for multiple repairs with independent causes (GM Canada Dealers Only).
- 10082869Aug 29, 2016This informational bulletin provides additional information on how to install pistons and suggest what tools to use.
- 10082814Aug 2, 2016This informational bulletin provides information to gm dealers on the correct cleaning methods when cleaning engine gasket sealing surfaces.
- 10201098Dec 1, 2015OEM and Remanufactured Engine and Automatic Transmission/Transaxle Identification
- 10190503Dec 1, 2015OEM and Remanufactured Engine and Automatic Transmission/Transaxle Identification
Engine: other model years
Other parts of the 2003 Chevrolet Trailblazer EXT 370
6 complaintsFuel system
3 complaintsExterior lighting
2 complaintsVisibility (wipers, defrost, mirrors)
2 complaintsElectronic stability control
1 complaintsEngine cooling
1 complaintsBody and structure
1 complaintsTires
1 complaintsWheels
1 complaints
← All problems reported for the 2003 Chevrolet Trailblazer EXT 370
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 30, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology