Cummins gave reporters an overview of how its heavy- and medium-duty 2007 engines will differ from current models as the engine maker prepares to roll out several “Beta prototypes” to select truck OEMs for final testing.
At a press conference held just before the Technology & Maintenance Council's annual meeting last month, Jeff Weikert, executive director of mid-range engineering, noted that the medium-duty product line for '07 would include a new beefed-up 6.7-liter ISB, replacing the current 5.9-liter platform.
The '07 ISB will offer 325 hp. and 750 lb.-ft. of torque, an improvement over current ISBs by 50 ponies and 90 lb.-ft. He also said Cummins' ISC (330 hp., 1,000 lb.-ft. of torque) and ISL (365 hp. and 1,250 lb.-ft. of torque) will be equipped with the same exhaust gas recirculation technology (EGR) currently used on the ISB platform.
Weikert added that 170 Beta prototypes of Cummins' entire mid-range line are scheduled for production starting in February, with 150 earmarked for fleets in the U.S. and Canada, and another 20 for the engine maker's engineering research team.
This follows 2.5-million miles of testing on medium- and heavy-duty '07 engines that began in May 2005 across multiple truck applications, including delivery vans and utility trucks, tankers, heavy haulers, garbage and dump trucks, as well as LTL and TL applications, he said.
Other key changes for the Cummins '07 mid-range line include a bigger 18-quart oil pan so that oil drain intervals can be extended to 20,000 miles, a new “coalescing filter” to clean crankcase emissions that needs to be replaced every third or fourth oil change, optional electronic oil level sensors, and an optional compression brake for the ISC platform.
On the heavy-duty side, Cummins was more circumspect about ratings for the '07 ISX and ISM platforms. However, Steve Charlton, executive director of heavy-duty engineering, stressed that ratings won't be reduced for the heavy-duty lineup.
The engine maker pointed out that the only additional subsystems on the '07 ISX are a coalescing filter to clean crankcase emissions and an exhaust dosing injector in the turbocharger to add minute droplets of fuel to the exhaust stream for active regeneration.
“Other than that, the '07 ISX looks a lot like the '02 ISX, with the exact same base engine design,” Charlton noted. “The stability of the base engine design, we think, gives us much better reliability.”
For the '07 ISM, all the emission-related components, including the EGR cooler, variable geometry turbo (VGT), and coalescing filter, will be on one side of the engine for easier maintenance.
Both Weikert and Charlton emphasized that DPF service intervals for removing ash buildup will range between 200,000 and 400,000 miles for the medium- and heavy-duty engine lines, depending on the vehicle's duty cycle, or 6,000 hours for a typical urban bus.
In addition, the filter Cummins plans to use for its medium- and heavy-duty products is designed to last the life of the engine.
Charlton added that only one DPF is going to be required for the engine, no matter the application or rating.
Cummins also expects about 1,000 distributors and truck dealers to be certified for warranty work by the first quarter of 2007. Both '07 model medium- and heavy-duty engines will be available for purchase in the fourth quarter this year.