Diesel exhaust fluid has been something service truck operators have had to deal with since the U.S. Environmental Protection Agency’s Tier 4 regulations have been phased in (and matched by their sister agencies in other jurisdictions, such as Canada).
While DEF is required in many diesel engines, service trucks are uniquely affected. Not only do many service trucks require DEF, but in many cases they are also a DEF delivery system for larger vehicles in the field.
Have the end users of DEF adapted to it usage in the time since its introduction?
“I bet we get a truck in here daily that has problems,” says Tyler Vanatta, service manager for Peterbilt of Garden City in Kansas. “They come in here with ‘check engine’ lights on and possibly the DEF gauge lights on. What we normally find is the tank’s been contaminated and the filters are plugged up in the lines. Sometimes, the injectors are actually plugged up or dripping and don’t shut off. We have some problems with the DEF pump module. But the most common is unknown contamination in the tank.”
Contamination also an issue at truck stops
Vanatta says that at first a lack of education was the problem because many users were unaware of how easy it was to contaminate DEF fluid. Now, however, he believes there’s a similar contamination issue at truck stops.
“We had guys filling their tanks with old oily funnels or carrying jugs of this stuff around with them,” Vanatta says. “They use the jug. What was left in the jug would dry out. They’d put more DEF in there. So then you’re dumping crystals in there. I don’t see so much of that any more. Most of the contamination we get in here, guys say they filled up at the truck stops out of a pump. I think that stuff sticks on the end of the nozzle and dries up and you get the same situation. They’re dumping that dried up stuff in their tank every time they fill up at one of those places.”
C&S Motors in Flint, Mich., only recently converted to DEF, having previously attempted to treat emissions in-cylinder, says Brian Klosterman, the service and operations manager. In his short experience dealing with DEF, though, Klosterman has seen the frustrations of his customers and experienced enough of his own.
“The whole after-treatment system in general, they’ve become a lot more complicated since 2007,” says Klosterman. “Nobody has any fun working on them. They fail a lot. Whether it’s the DEF system, the SRC (selective catalytic reduction) system, it’s very problematic. The biggest problem is that it’s not something you can send a local guy on. If he doesn’t have all the software, diagnostic training and tooling, there’s nothing he can do with it.”
Volume of problems causing long waits for fixes
Klosterman says that his shop is regularly swamped with trucks with emissions problems, to the point where most work has a two-week wait. He also says that it has been a financial hardship for dealerships who provide repair services. That’s because many of the DEF-related issues fall under warranty repairs – which are paid at a highly reduced rate.
“It’s been a huge financial impact,” says Klosterman. “When you’re working on an emissions system that, for example, takes 10 hours to repair and they only pay you (for) four of them. Warranty repairs can be 60 to 70 percent of a dealer’s revenue. That’s a huge loss when you’re taking a loss on every job.”
The other issue that has caused great consternation for users in more northern climates is DEF’s relatively high freezing point. Greg Liedl, the transportation coordinator for Bemidji Area Schools in Minnesota, says the first day back from Christmas vacation in 2014 had to be postponed because of cold-weather related issues, primarily frozen DEF.
“It all depends on the severity of the winter,” Liedl says. “We came off an 11-day hiatus from Christmas break and came back to 37 degrees below 0. What do you expect? All my stuff sits outside. My counterpart to the north of me at Red Lake, he’s got 52-degree indoor storage. He doesn’t have any problems. But if you sit outside for 11 days, you have to drop the tank. We had to drop the 15-gallon tank and let it thaw. There’s no fast way.”
Cold weather trouble for larger fleets
Liedl says while this is a minor issue for many school district transport coordinators who may only have one or two buses which use DEF, his fleet has more than 20. He does indicate, however, that a recent change in how the system reacts when it isn’t getting DEF has been beneficial.
“When it wasn’t getting DEF, it didn’t shut it down to the five per cent AP rating level. It took it down to, I believe, 45 or so. I can still chug along with that and pick up kids on a bus route. My buses don’t get up to highway speed all the time like an interstate trucker. I’m starting and stopping all over country roads and back area. I can motor along at that speed.”
Matt Henry, operations equipment manager for Vancouver Island Helicopters in British Columbia, Canada, says that his crews are often working in colder weather and the logistics of utilizing DEF fluid are contrary to the logistics of their job.
Cold-weather idling exacerbates troubles
“We did have other significant problems with DEF and emissions control equipment beyond it freezing,” Henry says. “Part of it was probably due to the trucks idling for longer periods of time. Often in colder temperatures, you might never shut your engines off and just let things idle. But that’s hard on emissions stuff and it tends to coke things up. We had a truck that got so badly coked that it plugged up the entire emissions system and backed right into the turbo of the engine. It was pretty much destroyed. They couldn’t even clean it.”
The end result is a system that users are wary of, and in many cases, will go out of their way to avoid. Some users told us about putting money into keeping older trucks running rather than purchasing newer models in order to avoid using DEF altogether. For Klosterman and many others, these issues must be addressed.
“They talk about (lowering) emission being a good thing, and it is, when they’re working right,” Klosterman says. “When they’re failing, they have the worst emissions you could ever imagine. My shop is stinkier now than it’s ever been. They’re not working properly most of the time. It’s frustrating, not just for the customers but for us. The problem is the system — this isn’t the final solution. This is a stop-gap method to meet emissions standards, but this can’t be the solution. Most of these trucks can’t get from one oil change to the next without going in the shop for some kind of emissions related problem. You talk to companies and drivers, people are angrier than they’ve ever been because of that stuff.”
Matt Jones is a freelance writer based in Fredericton, N.B.
