The transition to engines meeting 2007 emission standards was expected to be relatively trouble-free when compared to the early days of Exhaust Gas Recirculation. Yes, the 2007 standards introduced the industry to Diesel Particulate Filters...
The transition to engines meeting 2007 emission standards was expected to be relatively trouble-free when compared to the early days of Exhaust Gas Recirculation. Yes, the 2007 standards introduced the industry to Diesel Particulate Filters (DPF), but earlier generations of emissions-controlling equipment were rushed to market. This time, there was more testing. Even fuel supplies were upgraded to give the components some added protection.
Curtis Cummings, project manager for power vehicles at FedEx Freight, certainly offered a “good” grade when reporting on his experience during the annual meeting of the Technology and Maintenance Council (TMC). There was no change in Preventive Maintenance intervals. The fleet even continued to use existing CI-4 Plus oils without experiencing any filter plugging. Durability improved and fuel economy was up 1.8%.
Steve Duley, vice-president of purchasing at Schneider National, admittedly had a few more challenges. The base engines are reliable, but there have been defects linked to the DPF sensors and fuel dosing components, he said of the 1,876 power units now in service. The new engines also represented a 3% increase in work orders and more DPF regenerations than expected. Still, service was good and reliability has been improving.
The transition to the new technology has obviously presented some fleets with more challenges than others. In a poll of 120 fleet representatives attending the TMC meeting, about 60% said they faced more challenges with 2007 emissions hardware when compared to previous models. Sixty-nine per cent cited more maintenance issues, even though 67% noted that maintenance intervals were relatively unchanged. Fifty-eight per cent experienced more road breakdowns compared to the 35% who thought the experience was about the same.
Frank Nicholson faced his share of nightmares at TransAm Trucking, a long-haul refrigerated carrier that has recorded 120 million miles on 971 of the engines. “The list of problems is varied and lengthy,” the fleet’s vice-president of maintenance said. “Our overall scorecard for ’07 iron is unacceptable. There have been constant parts availability issues and we have been working our way through various campaigns and issues.”
Extended warranty packages skew true costs, but downtime has increased by 125%, with the length of time in the shop averaging four days and reaching as long as two weeks in extreme cases. “We incur out-of-route and deadhead miles just to cover a load and to maintain our on-time delivery percentages,” he added.
What went wrong specifically? Nicholson pointed to a litany of problems. Additional Preventive Maintenance steps were required for the thermostat, clean gas induction components such as the piping assembly, the crankcase filter, check valve and DPF. Parts costs jumped 37% and labour costs jumped 50% when the new equipment was compared to engines built prior to the 2007 emission guidelines.
The added maintenance requirements might even be a surprise to some users, he suggested: “Many fleets and even dealerships are not aware of the crankcase ventilation filter and the crankcase filter check valve.” It took three years before a supplier informed him about the check valve in the engine block, consisting of a small screen with a brass fitting.
It is now cleaned every 30,000 miles.
“Driveability has been acceptable – when you can drive it,” he said. “The EPA 2007 engine has been plagued with various campaigns and updates right from the start, and still continues to this day.”
Meanwhile, oil analysis programs showed unacceptable levels of iron, chromium, copper and aluminum. Some increases were as much as 30% over allowable limits. “We operated without SOS criteria for two or three years,” he notes, referring to how the allowable limits were unknown.
Thermostats are also requiring preventive maintenance every 200,000 miles to address overcooling. “Oil is emulsifying and plugging the filter,” he added. “When it fails, it’s in a stuck-open position.”
One of the few positive notes was that there was no measurable difference in fuel economy, but he largely contributes that to a more fuel efficient chassis. The regeneration of the DPF is still thought to consume more fuel.
Of course, most fleets seem to have challenges of one sort or another.
YRC Worldwide, an LTL carrier with 1,688 of the 2007 engines, required some additional engine programming to allow the Diesel Particulate Filter to regenerate when the vehicles were parked, said procurement manager Dan Miller.
“We weren’t getting enough regeneration going down the road based on climate condition, being cold, or light loads and short hauls,” he explained. Drivers also had to be trained to notify the fleet when related warning lights were lit.
“Distribute literature to drivers. Post things on bulletin boards so they know what to expect. Let them see what the icon is going to look like in the dash so they kind of know what to expect,” he suggested. “And one of the things we’ve had to stay on top of in our shop environment is to make sure mechanics have their software updates.”
Meanwhile, every driver at Schneider National receives one hour of training into the new engine technology, while general mechanics get a five-hour session and lead mechanics receive 35 to 40 hours of training.
Granted, the 2007 generation of engines still offer some of the worst fuel economy in the fleet at Schneider National. When compared to older engines, 2004 models were accompanied by a 4% increase in fuel consumption, and 2005 engines improved somewhat with a 3% increase.
The 2007 engines experienced a 5% sacrifice in fuel economy.
“Fuel economy has not been where it needs to be,” Miller agrees, referring to his fleet’s experience. But his fleet has tried to offset the impact using everything from fuel efficient tires to training.
As for the durability of the engines that are now in service? “I think that’s still being determined,” Miller says. “The jury’s still out.” MT