T56 6-speed transmission Archives - Transmission Digest
Evolution of the T56

BorgWarner designed the T-5 5-speed transmission that became one of the largest by volume of production. Using a very simple single-rail shift mechanism, the T5 was lightweight, came with a 5th-gear overdrive to add to fuel economy, and had a torque rating useable in engines of the period. The first T5 models used brass synchronizer rings and straight roller bearings to support the countershaft. BorgWarner refined the design and created “The World Class T5,” which used synchro rings lined with the same kind of paper material used in automatic transmissions, and went to tapered roller bearings for the gear train. The weak point of the T5 was its small size, which was easy to package in the diverse models of cars that used it, but with such a small centerline between the input and the countershaft, torque was limited to a high of 330 lb.-ft.

Six-Speed Solutions

The T56 now is found in Camaros, Firebirds, Dodge Vipers, C5 Corvettes, Aston Martins, the Australian Holden, Mustang Cobra R’s, the new Pontiac GTO and the just-released Cadillac CTS-V. Tremec also developed an aftermarket T56 unit that replaces the T5 units used in earlier Mustangs, Camaros and Firebirds. This unit is a direct bolt-in, which will require some modification to the cross member, driveshaft and, on Mustangs, the exhaust system.

Getting a Handle on Half a Dozen Speeds

In the 1993 model year GM introduced the T56 six-speed transmission in the F body cars (Camaro/Firebird). The transmission was designed and manufactured by BorgWarner Automotive and was an evolution of the earlier T5 design. Larger and capable of handling more torque and horsepower, this trans became an instant hit with performance enthusiasts, race teams and hot rodders.