Cummins Revamps Medium-Duty Engines for Stricter EPA Emissions Regulations
INDIANAPOLIS — Cummins Inc. unveiled its medium-duty engine lineup March 1 at the Work Truck Show here. It includes mechanical and electronic changes to meet greenhouse-gas emissions regulations, but it also features rebranding the 6.7-liter B series and the 9-liter L, reverting to displacement in the engine designation.
“Cummins is redefining classics — by introducing the newest-generation B and L Series engines — the B6.7 and L9,” said Brett Merritt, executive director of on-highway business for Cummins.
The B6.7 offers fuel-economy gains of up to 7% and new top ratings with a maximum 325 hp and 750 pound-feet of torque, according to Cummins. The engine is now offered in an economy range of 200 to 260 hp and performance ratings from 280 to 325 hp, with slightly lower economy gains of 5%.
The engine is optimized for stop-and-go duty cycles and is stop-start ready, according to Cummins. That means it is capable of switching off when at a standstill, but this ability has yet to be implemented because it requires interaction with transmission and vehicle manufacturers to make the feature available.
The B series engine traces its heritage back to a 5.9-liter displacement, 6-cylinder engine launched in 1984. Since then, more than 16 million midrange engines have been manufactured around the world, Merritt said.
The L9 is the 2017 iteration of the previous ISL with 260 to 380 hp and 720 to 1,150 pound-feet of torque. For vocational users, a new rating of 350 hp and 1,150 pound-feet of torque offers a wider rpm range for tough duty cycles.
The L engine has been available fueled by natural gas, as the ISL 9G. At the launch, the B diesel engine was displayed as a natural-gas engine for the first time, said Amy Boerger, vice president of Cummins’ North American engine business.
Cummins’ Connected Diagnostics telematics service is also offered on these midrange engines.
The company also displayed its repackaged aftertreatment solution, which puts diesel oxidation catalyst, diesel particulate filter and selective catalytic reduction systems into a single canister. This midrange aftertreatment system reduces space up to 70% for easier packaging on medium-duty chassis. It also reduces weight by 30% compared with Cummins’ current aftertreatment systems.
In other news from the show run by the National Truck Equipment Association:
• Ford Motor Co. launched an all-new Super Duty pickup range for 2017. The main feature is the use of military-grade aluminum throughout the cab, leading to significant weight savings.
The company also said that despite more use of high-strength steel in the chassis for greater stiffness, the new Super Duty is 350 pounds lighter than prior models.
The engine lineup will remain the 6.2-liter V-8 gasoline and the V-10, but revisions to the 6.7-liter Powerstroke diesel deliver 330 hp and 750 pound-feet of torque. With these changes, gross combination weight for the pickup is now at 40,000 pounds — half a tractor-trailer.
Additional details will be released closer to the start of production at the end of summer, said John Ruppert, general manager of commercial vehicle sales and marketing.
• Kenworth Trucks said the T880 is available for order with the Hendrickson Ultimaax severe-duty rubber suspension.
The Ultimaax offers a balance of empty ride quality and loaded stability for driver comfort, while also cushioning the load and protecting the chassis, cargo and body equipment from excessive vibration, Hendrickson said.
For the T880, the suspension is available with axle ratings from 46,000 to 52,000 pounds.
• Vocational customers of Mack Trucks using automated mechanical transmissions now have an option of deep reduction on the mDrive transmission.
An added front gear train gives the 12-speed transmission one or two extra-deep reduction ratios. The single deep reduction 13-speed gains a low of 17-to-1, and the 14-speed has two low ratios, a 19-to-1 and an extra-deep 32-to-1. The ultra-low ratio allows for low-speed crawling when pouring cement sidewalks and curbs.
• Mack also introduced its Clear Tech One, a lighter, more compact aftertreatment module that fits behind the passenger-side step. It is an option to the existing Clear Tech, two-unit separate diesel particulate filter and selective catalytic reduction modules. The single-unit component saves 17 pounds and frees up 11 inches of frame space.
• International Trucks said its DuraStar and WorkStar models will be available with an additional option, the Cummins ISL9, an 8.9-liter engine at up to 380 hp. This option adds to the range of engines that includes the company’s own N9 and N10, 9.3-liter engines at 330 and 350 hp and the Cummins ISB 6.7 liter at 300 hp.
