PEORIA, Ill. – Modifying your driving habits can result in significant fuel savings, says Russ Siegel, test and demonstration driver with Caterpillar On-Highway Engines.

Cat engines with ACERT technology must be driven differently than their predecessors, Siegel says, in order to obtain maximum fuel mileage.

“The biggest factor in fuel economy – good or bad – is the driver,” says Siegel. “Driving habits have a huge impact on fuel usage. It’s critical that companies educate their drivers on fuel-saving driving techniques, as well as specifying their vehicles to achieve the perfect balance of fuel economy and performance.”

First, customers must spec’ their vehicle properly, Siegel advises. Gear ratios should be lowered to operate at highway speeds at low RPMs. He says gear ratios of 3.42, 3.35 or 3.25 are the new reality as opposed to the past where 3.70 and 3.55 gear ratios were the norm.

“This lower gear ratio improves fuel economy and enables the driver to work in the preferred torque range for excellent performance,” Siegel says.

Peak torque on the new Cat engines is about 1,100-1,200 RPM, Siegel says, but peak torque isn’t reached until 1,500 RPM or higher.

“It’s pretty simple, really – by expanding the torque range, drivers can operate their Cat engines more efficiently and profitably,” he says. “Torque starts to fall off around 1,400 RPM – anything above 1,500 delivers a little more horsepower, but eats fuel. Heavy haulers may need to operate that high at times, but should try to avoid it when possible.”

Siegel says hills should be ascended at about 1,100 RPM. If a downshift is required, it should be done at 1,250 or 1,200 RPM to keep momentum up and reduce the number of downshifts required. He says Cat engines can be lugged when climbing grades.

Siegel also insists drivers can improve their fuel economy by better managing their speed while cruising down the highway.

“It’s important to remember to keep vehicle speed down – fuel economy drops by .10 mpg for every mile per hour over 55. And, you’ll maximize fuel economy if you operate in the highest gear possible, so cruise in top gear,” he says. “At the same time, keep the engine below 1,500 RPM, downshifting at around 1,100 RPM. Use progressive shifting techniques by upshifting around 1,400-1,500 RPM in the upper gears, and 1,100-1,300 RPM in the lower gears. Remember to use cruise control whenever possible to maintain average speed and good fuel economy.”

Drivers should avoid running the fan while driving, unless it’s required, since the fan draws horsepower. Siegel suggests leaving the fan switch on automatic mode.

He also reminds drivers to reduce idling, as the new engines don’t require long cool down periods.