MACK Trucks has added a new 10-speed gearbox to its line of T300 Maxitorque ES transmissions. The new T310 was shown during the Mid-America Trucking show in Louisville, Kentucky, March 19 to 21, 2003.

Designed primarily for highway applications, the new transmission is available in the Mack Vision, CH, and Granite models. It can be matched to any of Mack's ASET engines and is ideal for daycabs and small to mid-sized sleeper tractors for regional applications, the company says.

The T310 uses a conventional 10-speed shift pattern with 39% steps with the same smooth shifting of other Mack transmissions. It has a 19.04 overall ratio for a wide operating range. First gear is 13.81:1 for low speed gradability, and tenth gear is a 0.73:1 overdrive ratio.

Housed in an aluminum case, the T310 weighs 665 lb. It has both six- and eight-bolt power take-off mounts for auxiliary equipment operating at 70% of engine speed. The transmission uses a triple-countershaft design that distributes stress throughout the gearbox. Mack backs its claims of transmission durability with a five-year, 750,000-mile warranty. The warranty covers transmission operation with either mineral or synthetic gear oil in applications with change intervals of three years or 500,000 miles.