Rex Kuhn, application engineer for International Truck and Engine Corporation's medium product center, and Bill Frazier, severe-service product manager, said they had “great news” for medium-duty vocational customers and body manufacturers: The company's decision to go with an in-cylinder NOx reduction system setup means very little change for the 2010 models.
“We're not adding any equipment to the aftertreatment,” Frazier said. “We're not moving the battery boxes. We're not moving the air tanks. As far as the chassis is concerned, 2010 is going to be rather invisible.”
Said Kuhn, “2007 presented a lot of challenges making everything fit, presenting the packages you needed. With a urea system packaging, there are extra components involved that would take you out on the chassis and things that would interfere with your equipment and body mounting. We're not going down that path.”
International announced in November 2007 that MaxxForce brand diesel engines would meet the US EPA 2010 emission standards for all its core applications without the use of selective catalytic reduction (SCR) systems, saying that SCR comes at a steep price to customers in terms of cost and inconvenience.
Instead of SCR, International will address 2010 emissions requirements through advanced fuel system, air management, combustion, and electronic controls, with no incremental NOx aftertreatment beyond the current technology. All MaxxForce on-highway diesel engines used in International's core applications will be fully certified to the EPA 2010 emission standards.
International MaxxForce engines are used in on-highway Class 4 to Class 8 commercial trucks. In North America, the MaxxForce product line ranges from a 4.5-liter V6 to two new MaxxForce big-bore Class 8 engines that launched earlier this year.
Kuhn said it will be business as usual for fleet operators.
“There will be no technician and driver training, no increased maintenance,” he said. “No added tanks, lines, sensors, electronic control units, catalysts, wire harnesses, heaters. No monitoring, no hunting for or adding urea. No urea cost tracking. No freezing urea.
“We've improved our HVAC system with improved air flow, improved filter access, and removal of thermistors. The air filter has a flat-panel filter element, and there's increased filter life and easier access for service.
“Some of you might be affected with some of the improvements we made. At the front of chassis, only with 285 hp and above, there's a 6×4 crossmember and a lower profile steering gear. The housing has been redesigned. We have a left-side megabracket. With the DuraStar or old 400 series, in 2007, we had to come off with a right-side megabracket with increased cooling. With the 2009-2010 285hp, we're putting in a left-side megabracket. Anybody mounting equipment at the front of the chassis, you need to be aware of that. That's the major change we made on the chassis for 2009-1010.”
He listed these medium-duty product enhancements: hybrid electric vehicle and Class 6 4×4 vehicle in March, special step package (Code 16ZZA) in April, a 14,000-lb front axle up to a 272' wheelbase in May, AutoTherm anti-idling energy recovery system in June, and quadralic brakes, and Electronic Stability Program (ESP) in July.
And these severe-service enhancements: 10” rails and 22,000-lb front axles in November, sleeper cab in January 2009, Firemax suspension in February, oil-field features in April, and tridem rear axles in September.
Big reductions
Engine marketing manager Al Ambrosini said that in 2005, they were treating NOx at a level of 2.61 g/bhp-hr in Europe, but US 2010 regulations require 0.2.
“Going into 2010, we're looking at a 96% reduction in NOx and 90% in particulate matter,” he said. “We started this program prior to 2004, looking forward to reduced levels, and started doing our engine homework. It's getting more complex, but we feel we are on top of it.
“With in-cylinder, to reduce NOx, we burn diesel fuel the way it's burned today, but through improvements in combustion and engine actuation electronics. With SCR, they use combination of diesel fuel and injecting urea into the aftertreatment device. That does the work cleaning the exhaust gases to the proper levels. Both work. It's just the method you want to use to get there.”
He said the SCR system results in an additional weight of 300-400 pounds, with an SCR catalyst, pump, doser, valves, lines, electronics, and harness — thus decreasing payload. He said urea freezes at 12 degrees F, requiring a heated tank and lines.
“It's a very precise system, with electronic controls and valves, and a heater control,” he said. “There's added training — driver and technician training to replenish and maintain the system.
“There are SCR performance issues. Urea usage is 2-5% of the fuel consumed. Fuel economy would need to be better by more than 2-5% to offset the cost of urea, assuming urea is the same cost as diesel. Urea prices are similar to diesel prices today but are expected to increase as demand increases. The urea solution has a set shelf life and requires a tamper-proof design. If the urea tank is not refilled, the truck may need the disable mode to ‘limp home.’ Urea may require additional low-level warning lights and driver notices.”