Allison Transmission Inc. announced that its customer Pinellas Suncoast Transit Authority (PSTA), which serves the Tampa-St.Petersburg-Clearwater, Fla. metropolitan area, found a 56 percent fuel economy gain for their buses equipped with the Allison Hybrid Ep40 compared to standard diesel buses.

PSTA deployed 10 Gillig buses equipped with Allison's Hybrid Ep40 nearly a year ago and has been running fuel consumption comparisons against its standard diesel buses.

The agency reported that its 10 hybrid equipped buses got an average of 6.4 miles per gallon (MPG) compared with 4.1 MPG for their standard buses.

"We were expecting fuel economy increases of approximately 20 percent over standard diesel buses, so this substantial improvement of 56 percent goes even further in doing what's best for our budget and the environment," said Tim Garling, PSTA's executive director.

The Allison Hybrid Ep40 is a two-mode parallel hybrid that operates automatically as a parallel hybrid or series hybrid. The continuously variable drive features an infinite number of ratios and automatically adjusts ratios to operate at optimum power curves, attaining the best performance and fuel economy.