Class 6 Truck Market Moving to Four Cylinder Engines
New Isuzu FTR, Others Going to I-4 Diesels
The engine downsizing trend for trucks came into the limelight in 2011 when Ford introduced the 3.5L EcoBoost GDI turbo V-6 in the F-150. Since then, Ford has introduced a 2.7L EcoBoost, Ram has come out with the 3.0L EcoDiesel V-6 in the Ram 1500, and the 3.6L Pentastar V-6 effectively replaced both the base 3.7L V-6 and 4.7L V-8 in the Ram. Now, the engine downsizing trend is starting to move into the medium-duty commercial truck market, according to a report from Trucks.com.
While the transition among 1/2-ton trucks was from V-8 to V-6 engines, for these bigger commercial trucks, the change is from I-6 to I-4 diesels. Leading the charge into smaller engine displacements are Freightliner and Isuzu. Freightliner will offer its M2 Class-6 truck with a 5.1L I-4 diesel engine for the 2017 model year. The new 2018 Isuzu FTR will offer a 5.2L I-4 diesel, the same displacement as previously offered in the smaller NPR cabover trucks and replacing a 7.8L I-6 diesel. Some of the NPR models are now offered with a 3.0L diesel in place of the 5.2L engine, which is still offered in heavier-duty trims. As installed in the NPR, the 5.2L engine makes 215 hp and 452 lb-ft of torque. Power and torque outputs are expected to be higher for the FTR application.
According to the report, most drivers have not complained about the reduced power or even notice the change. Only in higher-elevation areas is the reduced power noticeable. As with light trucks and passenger cars, the move to smaller engines is being driven largely by tougher fuel economy standards on the horizon for commercial trucks.