Chevrolet Colorado GMT355
Weaknesses, engine ratings and buying advice
242 PS
Colorado · Benzin
3.7 I5 — the better five-cylinder
Decent245 PS
3.7L I5 Benzin
2 weaknesses
Good ChoiceGenerations
Engine Overview
The Chevrolet Colorado GMT355 is available with 4 engine variants — from 177 to 245 hp.
2.8L four-cylinder, base engine for the first-gen Colorado. 175 hp, mechanically simple and reliable. Same Atlas platform as the I5 but without the valve seat catastrophe. The 4L60-E auto is the bigger concern.
No known weaknesses documented.
2.9L four-cylinder, replaced the 2.8L LK5 in 2007. 185 hp, more refined. Common issues: thermostat, water pump, engine mounts. The most economical choice if power is not a priority.
No known weaknesses documented.
3.5L inline-5 from GM's Atlas engine family. Distinctive five-cylinder sound. The cylinder head valve seats are the fatal flaw: they lose their seal from around 100k mi. GM extended the warranty for 2004-2006 to 7 years/100k mi. Revised heads with harder valve seat material are the fix.
- !! Cylinder Head Valve Seat Failure (3.5L I5) from 107,000 km
Intake valve seats in the 3.5L I5 lose their seal over time, causing misfires. GM extended warranty to 7 years/100k mi for 2004-2006.
Symptoms: Misfire codes P0300-P0305, rough idle, Check Engine Light - !! Head Gasket Failure (3.5L I5) from 130,000 km
Coolant mixes with oil, milky oil cap, overheating. Repair complicated by timing chain removal. Heads often warped, require machining.
Symptoms: Milky oil cap, white exhaust smoke, overheating
3.7L inline-5, replacement for the 3.5L with revised cylinder heads. 242 hp, well-suited torque for a small truck. Valve seat issues improved but not eliminated. Water pump and thermostat failures common around 100k mi. A solid truck engine that runs 200k+ miles with regular maintenance.
- !! Cylinder Head / Valve Seat Issues (3.7L I5) from 120,000 km
The 3.7L I5 improved upon the 3.5L valve seat issues but did not fully resolve them. GM issued an internal bulletin for specific VINs.
Symptoms: Misfire codes, rough idle, Check Engine Light - ! Water Pump / Thermostat Failure from 100,000 km
Water pumps and thermostats are common wear items on the I5 engines. Failure typically around 100k mi. Fan clutch can also seize.
Symptoms: Coolant leak from water pump, overheating at idle, temp gauge rising
Vehicle Weaknesses
| Weakness | Cost | |
|---|---|---|
| Frame Rust (Salt Belt) Box frame design traps water and road salt, causing severe frame corrosion. Driver-side rear near leaf spring is the first failure point. Aftermarket frame repair kits (Rust Buster) available but costly. Symptoms: Visible rust on frame rails, truck bed contacts cab, fails inspection from 130,000 km | High |
Top Reported Issues
Alternatives
Explore more
Known Problems and Issues +
A total of 9 weaknesses have been documented for the Chevrolet Colorado GMT355 (2004–2012) — 4 engine-related and 5 vehicle-related. Typical issues affect Rust, Gearbox, Electronics. Considered reliable: LLR (3.7L I5).
Colorado (L52, 2004–2006) — Be Careful: Cylinder Head Valve Seat Failure (3.5L I5), Head Gasket Failure (3.5L I5). Power: 220 PS.
What to watch out for with the Chevrolet Colorado? See the detailed listing of all engine and vehicle weaknesses in the sections above.
Frequently Asked Questions
What problems and weaknesses does the Chevrolet Colorado GMT355 have? +
What should I look for when buying a used Chevrolet Colorado GMT355? +
Which engine is recommended? +
Which Chevrolet Colorado GMT355 engine is the most reliable? +
Which Chevrolet Colorado GMT355 engine is the most fun? +
Is the Chevrolet Colorado GMT355 worth buying used? +
What horsepower variants are available for the Chevrolet Colorado GMT355? +
Last updated: February 2026 · All information without guarantee