They feature dual overhead camshafts, variable valve timing, electronic throttle control and other features that contribute to high levels of operating efficiency and fuel economy. Balance shafts help ensure smooth operation of the engines, providing a higher level of refinement.

In addition to their larger displacement - delivered through larger, 3.76-inch (95.5 mm) bores - the 2.9L and 3.7L engines feature improved airflow in and out of the combustion chambers, which helps boost power. They also share additional upgrades and changes, compared to the previous Chevrolet Colorado engines:

- Larger, 1.52-inch (38.7 mm) intake valves, vs. previous 1.45-inch (37 mm) intake valves
- Larger, 1.32-inch (33.5 mm) exhaust valves, vs. previous 1.18-inch (30 mm) exhaust valves
- Revised camshaft profile optimizes valve lift and duration in accordance with larger valves
- Cylinder head airflow increased to match capabilities enabled by larger valves and revised camshaft
- New, noise-reducing oiling system uses cylinder wall squirter system enabled by a hole in each connecting rod that delivers a precise oil stream onto the cylinder wall beneath the piston
- New aluminum camshaft cover helps reduce noise
- Tighter-clearance balance shaft bushings promote quieter operation
- New, 2-megabyte powertrain control module houses new diagnostic information storage
- New cartridge-type engine block heater, which fits neatly into a specially machined block orifice; for used with available engine block heater.


Additionally, the 3.7L five-cylinder engine has several features that help it meet new BIN 5 emissions requirements, including a larger, close-coupled catalytic converter and A.I.R. system.

Transferring Chevrolet Colorado engines' torque to the axles is an Aisin five-speed manual transmission or a Hydra-Matic 4L60 electronically controlled four-speed automatic. The manual transmission is standard with the four-cylinder engine. The automatic is standard with the five-cylinder engine and available with the four-cylinder.


Chevrolet Colorado 2007 Safety features

Chevy Colorado has standard dual-stage frontal air bags with a passenger sensing system. Dual-stage frontal air bags are designed to help reduce the risk of air bag-induced injury. When the air bag system's control unit detects an impact, it determines whether the crash is severe enough to trigger a deployment, and whether the primary amount of inflation is sufficient. The primary stage alone will deploy in most frontal impacts requiring the supplemental protection of an air bag, while a secondary stage is designed to deploy in more severe frontal collisions.

Chevrolet Colorado also offers head curtain air bags for enhanced side-impact protection - the first vehicle in the segment to offer side air bags. The optional head curtain side air bags act like a protective curtain when deployed, unfolding from the roof rail between the A-pillar and side window header. When the bag deploys in a moderate to severe side impact, it is angled somewhat toward the window to help provide protection for front- and rear-seat outboard passengers.

Pretensioners at the outboard front-seat positions deploy at the same time as the frontal air bags to take up slack in the safety belt webbing. Pretensioners also help reduce the amount of occupant movement in the event of a crash to help reduce the risk of injury.

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