One mpg doesn’t sound like a whole lot on its own. But when you consider a 324-truck fleet traveling hundreds of thousands of miles every year, one mpg improvement per truck adds up – in both fuel and environmental costs.

Chrysler Group LLC is considering those costs closely as it works to replace its entire Transport fleet trucks. The trucks deliver parts from suppliers—mostly from the company’s stamping and powertrain plants, but also from some outside suppliers—to Manufacturing’s assembly plants and Mopar®’s parts distribution centers. The group operates terminals in Detroit, Toledo, Ohio, and Windsor, Ontario.

The savings to come from the new fleet, which will number 324 trucks, are many. The new vehicles will save money on leases, use less fuel and require less maintenance, Jean-Paul “JP” Barrette, Head of Chrysler Group Transport Inc., said. The vehicles, all of which meet the new and tougher 2010 U.S. EPA emission standards, will cut emissions by 85 percent.

Earlier this month, officials at the group’s Detroit Terminal took delivery on their first new truck in nearly five years. The vehicle, a new Mack Truck Pinnacle Series day cab highway hauler, was the first the company will lease and add to its three terminals.

The Mack trucks will provide about a 5 percent improvement in fuel economy, according to Dave Costello, Operations Manager at the Detroit Terminal. That’s about 1 mpg better than the current models the company now uses. The current trucks get a little better than 6 mpg on the freeway while the new Mack truck should yield about 7 mpg, Costello said. They also represent something larger.

“In the big scheme of things, I say these trucks are delivering a sense of renewal and optimism,” Costello said. “It’s tangible evidence of what a difference a year can make. We’re refreshing our fleet. We have a future. We’ve survived and we’re moving forward.”