The new 2023 Chevrolet Colorado and GMC Canyon come exclusively with the brand’s now well proven 2.7-liter turbocharged 4-cylinder truck engine. Notably, the engine program was initially designed first for the Colorado pickup even before its use in the Silverado and Cadillac models. It just so happened the Colorado development hit delays and ended up not being the first vehicle to showcase the engine as originally planned.
Different from the full size trucks, Cadillacs and even the GMC Canyons however, the Colorado’s engine is offered in three power output levels with two distinctly different mechanical versions.
The base engine only available in the Colorado WT trim grade is known as the L2R has a lower output level of 237 horsepower and 259 pound feet of torque. It has a maximum turbo boost of 10 psi and is mated to an 8L45 8-speed automatic transmission. The powertrain offers up to 3,500 pounds of towing capacity.
The top engines optional in the WT and LT, and variants standard in the Trail Boss, Z71 and ZR2 are based on the L3B version. The first called Turbo Plus offers 310 horsepower and 390 pound feet of torque with 20 psi boost. The HO variant has 310 horsepower with 430 pound feet of torque with up to 27 psi boost. These are both mated to a heavier duty next-generation 8L80 8-speed automatic and offer a towing capacity of 7,700 pounds.
A neat hack was shared by Chevrolet at our press briefing in that if you optioned the mid-level Turbo Plus, stepping up to the HO performance level after your purchase is as easy as going to your Chevrolet Dealership and getting the HO calibration installed through the accessories program for a few hundred dollars. Nice huh?
On the flip side, while the base WT base L2R engine shares all of its major specifications and core hardware with the more powerful L3B versions, it’s was intended for fuel efficiency and lower cost. In such, it’s mechanically de-contented compared to the L3B and loses items like piston cooling jets and foam noise shields among other ancillary items among other things that lend it to refinement and longevity at higher output levels.
Engineers from Chevrolet stated that it could feasibly be tuned to give the same output of the more powerful L3B versions but the engine and its lighter duty 8L45 transmission would likely not last very long. The exact words from head powertrain engineer were, “you could do it but things will break”.
All three variations of the engine share common specifications like a 10:1 compression ratio and 6,100 rpm redline and most notable – are recommended to use 87 octane regular unleaded. Direct fuel injection is standard, the entire assembly which is mounted at the side of the head just below the composite plastic intake manifold. The can driven fuel pressure regulator can be seen on top of the engine’s valve cover.
Chain driven dual overhead cams have variable timing and offer sliding sleeves that enable three different lobe profiles on the fly. There are two lift profiles for high and low and a third set that along with active fuel management can shut off cylinders 2 and 3, allowing the engine to run only on 1 and 4 to save fuel in situations where the extra power isn’t necessary – indicated to the driver by the ECO icon being illuminated on the instrument cluster.
In such the aluminum head features an integral exhaust manifold with three outlets, one each for cylinders 1 and 4, a shared outlet for cylinders 2-3 flowing into into a BorgWarner dual-volute liquid cooled turbocharger with an electronically controlled waste gate. The primary catalyst is directly attached for better thermal management. Intake air is cooled with an air to air inter-cooler before entering the composite plastic intake manifold.
The engine itself features a rigid deep skirt aluminum block with forged steel crankshaft and bearing caps along and forged steel rods with tri-metal bearings. The cylinders feature steel liners for durability.
To keep it all cool the engine features a comprehensive external and internal cooling system with an electric water pump that can run at different speeds regardless of what the engine is doing. When engine is idling or off in high heat situations, it can keep coolant flowing to prevent boil over.
Coolant flow is orchestrated by the main computer and executed with a 3-way rotary valve system found under the intake manifold that sends coolant where ever and whenever it’s needed including its external oil and transmission coolers which are themselves water cooled as well as cabin heating during warm-up.
Deep in the structural aluminum oil pan you will also find a continuously variable oil pump helps to lower parasitic losses as well as providing proper lubrication and cooling to the engine, especially under high-load conditions.
Stepping back and noting a few last details I missed in the walk through, because of electric power steering and its electric water pump, the only belt driven engine accessories are the alternator and the AC compressor. And obviously the production engine is not all chromed out and detailed like this nice display piece.
Both the L2R and L3B engines are built at GM’s Spring Hill Manufacturing plant with the majority of its internal and external components also sourced from North America.
