Combustion v. Compression

Do medium-duty trucks run better on diesel engines or gasoline power? If you only consider the price at the pump, you may be missing the bigger picture Web Extra!

"Really, when we broke it down, we were spending thousands less per (gasoline-powered) truck with the post-2007 diesels coming out and gas trucks essentially staying the same price," he says. "It was significant, so that was the rationale for starting the switchover."


It wasn't hard to convince the franchisees to switch over, despite Joost's estimate that "You'll always have five or ten percent who are hard-core diesel guys." Those hard-core diesel guys are not being forced to change their ways, but the company lets them know what they'll be dealing with if they continue to spec' diesels. Delivery time will be longer, for one thing, because the company only has gasoline models on reserve with Isuzu, the purchase price will be higher, and the company's long-term analysis shows that there will be cost-of-operations implications for the life of the truck.

"So, there are some qualitative and some quantitative measures that we've looked at," Joost says. "We didn't just make this decision out of the blue."

On the qualitative side of the decision, franchisees must consider the age and experience levels of their drivers. "They're not professional drivers," Joost says. "When you look at post-2007 diesel trucks with DPF regeneration and all the extras that come with it, (gas) was a lot easier.

"When you look at the actual everyday use of employees--their turnover rate is on average eight or nine months, because they're students and they go back to school or move on--these aren't long-haul drivers, or owner-operators of the truck," he says. "So, we wanted to get the cabover because the size of the truck is specific to these guys feeling comfortable driving the vehicle, and the gas application, for the average person in North America, is what they're used to. All that adds to their comfort level and confidence, which we feel translates into a safer operation."


To those who argue that the fuel economy gain you get with a diesel engine trumps all other considerations, Joost offers an alternative view. First of all, he believes that, in the post-2007 world, the lower lifetime fuel consumption of a diesel engine doesn't offset the higher initial purchase price or the higher cost of a gallon of diesel fuel.

Further, even this early in the program he sees a difference in maintenance expenses.

"If anything, this is actually reducing maintenance costs overall," he says, "just with the parts for gas trucks being cheaper and easier to get than those for diesels. They're just cheaper to work on in general.

"We still don't have numbers that show the frequency with which the trucks are going in for service, but that is something that we are looking at to say, ‘Listen, a part for a diesel costs $500 while the same part for a gas engine costs $270, but are you replacing it twice as much?' But we haven't gone far enough into the life of the gas trucks, because they're only a year old."

Joost also finds that it is easier for franchisees to find skilled technicians who can work on gasoline-powered trucks. While the company encourages franchisees to have trucks serviced and maintained at Isuzu dealers, some don't have access to the dealer network and have to fend for themselves.

"We're in 44 states, and we go from rural markets right into downtown Manhattan, so there is definitely a benefit to someone who is, maybe, in Idaho in a rural town who has a local mechanic who can work on the truck when there isn't a dealership within 150-200 miles," Joost says.

"It's tough, if you have two trucks in your operation, to drive four or five hours for a service."


"I don't have anything against diesels," Joost proclaims. "And I'm not a huge proponent of gas in the same way. But for our business application I am, just because it makes sense for our guys and the size of the business and the initial capital investment in these trucks. If they can save $10,000 to $15,000 on buying two trucks--because they have to when they start the business--that's significant, because that could be operating capital. It just makes sense for us."

For other applications--say, those where the truck clocks 30,000 to 50,000 miles a year--Joost admits that gas engines wouldn't be the right spec'. "It probably wouldn't make sense, because by year four or five they will already have gone to what we feel is a comfortable mileage on a gas engine," he says.

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