The Chevrolet Colorado pickup and Trailblazer SUV will be getting a new powertrain soon with the introduction of the second-generation Duramax four-cylinder turbodiesel. The MY14 Duramax will continue to have the same 2.8 and 2.5 litre displacement variations as found previously, but significant re-engineering has resulted in increased output.
The new Duramax 2.8L is capable of 200 hp and 500 Nm of torque at 2,000 rpm, up from the 180 hp and 440 Nm (also at 2,000 rpm) on the current Duramax. The new 2.5 litre unit churns out 163 hp and 380 Nm, an increase of 13 hp and 30 Nm over the existing engine. Both are Euro 4-compliant, but can be upgraded to meet Euro 5 and 6 standards.
The company says that the engine has been made stronger to handle the increased outputs, and certain elements have been redesigned to enhance durability and further improve overall quality. There’s a new common-rail system, which is capable of up to 2,000 bar (29,000 PSI), and to extend engine life – as well as that of the variable-geometry turbocharger – the 2.8L variant gets water-cooling to its turbocharger and turbine housing.
Elsewhere, there’s a new electrical exhaust gas recirculation (EGR) valve that comes with a bigger cooler for added precision and efficiency, while reducing nitrous oxide emission. Also on, a redesigned, lighter and higher efficiency intake manifold, which helps improve overall engine performance.
Also redesigned are the cylinder head and cylinder block, both lighter but with increased cooling efficiency. Finally, a balancer shaft has been added to reduce vibration/noise and promote smoother operation. The units also feature a new engine control module, featuring newly-developed software, for quicker response and added accuracy.
The six-speed transmission, meanwhile, has also been retuned to take advantage of the engine’s output characteristics while enhancing economy, the company adds. The MY14 Duramax, which will be built at the GM Powertrain facility in Rayong, Thailand, will first be seen on the Thai-built Trailblazer.