DARTMOUTH, N.S. – So you’re buying a new truck, eh?

No matter the manufacturer you choose, the procedure for picking an engine – one with the power you need but reasonable on fuel – is the same. The order you dance those steps can vary dramatically, mind you.

Murray Broughm, a territorial sales representative with Cummins Eastern Canada, out of Dartmouth, N.S., believes in a start-at-the-engine-and-work-back method.

“Basically you take your engine, your horsepower, your transmission, your rear-axle ratio and you marry it all up and … you try to give him the road speed that he wants to run,” says the spec’ing guru. “With that road speed, then we try and determine the most efficient spot on the engine for fuel mileage and performance, to give him the best of both worlds.”

According Caterpillar’s Jim Booth Jr., a truck operations specialist, the engine is the last decision you make.

“(The buyer) needs to figure out exactly what he wants to do with the truck, and when he goes to figure out his spec’s, (he works) from the ground up,” Booth says. “Starting with what tires he wants to have in it, what rear-ends, what transmission.”

No matter what order you work in, you’ll eventually end up with a spec.

And how all this iron will look once it’s pieced together, Broughm insists, is really dependent on two things: where you hang your hat and where you plan to run.

“Basically you’ve got two sets of rules,” says Broughm, whose 14 years in the industry have earned him the status of “resident-expert spec’er” around the office.

“There’s one spec you take if you’ll be running the U.S. – that same spec will work for Montreal to Toronto – and out west some, depending on the terrain.”

He insists, however, that regional carriers in Atlantic Canada have some unique concerns all their own.

“The East Coast is totally different, it requires a little different spec’ing,” says Broughm.

“It’s a little more aggressive: you need more gradeability and startability.”

He says your horsepower will need to be at least 460 or higher.

“Rear-axle ratios will depend on whether he’s hauling tri-axles or B-trains,” contends the spec’ing guru. “Tire size also comes into play for gradeability.”

Robert Keens, market-development manager for Cat’s Truck Engines Division, adds drivers will often make one inadvertent mistake when buying a new engine: they don’t follow through on their preferred spec’s.

“Everyone will like those specifications … but when the guy goes out and actually buys something – particularly off the lot – there may be tall rubber instead of short rubber, for example,” says Keene.

“He’s not going to get the performance he’s expecting at that point.”

You have to make sure you buy what you spec, both Cat representatives agree, adding that even one variable will change the entire equation and throw the vehicle out of its optimum range.

“They have to make sure everything is the same,” says Keene.

“From the name brand of the tire all of the way through.”

Broughm insist this single variable may exist in an engine, without the buyer’s knowledge, if the electronics haven’t been properly programmed.

“It has to be set to meet (the buyer’s) needs and the owner has to understand the engine settings and capabilities,” he says.

“And most importantly, the driver of the truck has to understand exactly what he has and how it works.”

A poor understanding of how a truck is set will reflect back, in the form of poor fuel mileage, extra shifting on hills or in a number of other ways, he insists. “If the top gears are set and the driver doesn’t understand the settings, in some cases, it could be a safety hazard,” Broughm points out.

“He may pull out to pass a car and all of a sudden the thing shuts off,” he says. n