Chevy Colorado uses eight-speed auto to sip, not swig
Their shape hasn't changed much, but modern trucks are smarter than their ancestors. Smart material mixes are making them lighter and stronger, and smaller turbocharged powertrains have opened the door to improved fuel efficiency with no payload penalty. Chevrolet has given its Colorado a smartening up, fitting an eight-speed gearbox and a thoroughly reworked V6 for better performance and economy.
Under the hood, there's a thoroughly reworked version of the DOHC V6 featuring in the current car. The variable valve timing on the intake and exhaust have both been tweaked, and improvements in the direct injection system should help to eke out a few extra mpg, though no fuel economy figures have yet been released. There's cylinder deactivation, too, shutting down two cylinders under light loads.
Peak power has been bumped from 305 hp to 308 hp (227 to 230 kW), and the 373 Nm torque peak is an 8 Nm improvement over the what the old engine could manage.
Working in tandem with the new, more efficient engine is GM's new eight-speed gearbox. Physically, it's almost exactly the same size as the outgoing 6L80 six-speed 'box, and the extensive use of aluminum and magnesium mean there's no weight penalty associated with the extra ratios.
Because there's more ratios squeezed in, the new Colorado's lower gears can be shorter for punchier off-the-line acceleration, while top gears can be taller for quiet, efficient running at highway speeds. Chevy says this is the first midsize truck to run with an eight-speeder, and only the ten-speed Ford Raptor can outdo it across the whole truck segment.
The new Colorado, with its new V6 and eight-speed automatic, will be in dealerships before the end of the year.