Engines/Drivetrains
Paccar’s proprietary 12-speed transmission
MT VERNON, WA - Paccar has unveiled a 12-speed automated transmission, rounding out a proprietary powertrain with the promise of better fuel economy and smoother shifts along the way. Developed over three years in a partnership with Eaton, the transmission will be released into the market this October. "The Paccar automated transmission is engineered to work seamlessly with Paccar MX engines and Paccar axles," says Landon Sproull, Paccar vice president. It will support linehaul applications with Gross Vehicle Weights up to 110,000 pounds, and engines delivering up to 510 horsepower and 1,850 lb-ft of torque. The first units will be an option with MX-13 engines.
TransPower’s Totally Electric Class 8 Truck
True zero-emissions freight transportation is closer to reality than you might think. TransPower USA has five Class 8 tractors currently in service at the Port of Long Beach, CA. The company also has several yard shunt tractors and school buses in real-world service. These trucks are not cobbled together McGiver jobs, either. They are highly engineered and look just like factory installations. These trucks could be the long sought-after solution to diesel emissions in areas with real air quality issues. We recently had a opportunity to test drive one of these electric Class 8 trucks and found it to be a very functional alternative to a diesel tractor. We had the truck without a trailer, so we can't report on its pulling power, but the company says the truck is powered by two 200-hp electric motors. That's 400 horsepower, plus you get the benefit of the very high torque output of the electric motors.
Dana’s Dual Range Disconnect
First revealed at the Mid-America Trucking Show in March, Dana's Dual Range Disconnect drive axle system offers the fuel savings benefit of a downsped 6x2 drivetrain and the performance benefits of conventional 6x4 setup with a mid-range axle ratio. The key word here is disconnect. While running at speeds up to about 54 mph, the system functions as a 6x4 with torque going to all four wheels for optimum traction. It also runs at a 3.10:1 ratio for better performance and startability. Above 54 mph, the interaxle driveshaft disengages, leaving the driving to only the forward drive axle. Interestingly, the axle ratio of the forward axle is 2.26:1, which lowers engine rpm and in effect creates a downsped drive train. The benefit, of course, is better fuel economy resulting from a 300-400 rpm drop in engine speed.
