In 1998, General Motors began selling of heavy-duty trucks Isuzu F-series in North America under the brand names GMC and Chevrolet. These models were designated as the T-series. The range was divided into three series of different capacity – T6500, T7500 and T8500. They were equipped with different engine rated at 177, 203 or 273 hp.
In 2008, Chevrolet T-Series received more powerful and more torque 6H engine, along with new six-speed Allison transmissions, and a vertical Diesel Particulate Filter (DPF) option. For T6500 and T7500 customers, the standard transmission is an Allison 2500 Series six-speed with a GCWR rating of 33,000 lb. Also available is the Allison 2200 Series close-ratio six-speed transmission with integral park pawl and GVWR/GCWR rating of 26,000 lb., and a 2550 Series wide-ratio six-speed transmission with integral park pawl and a GVWR/GCWR of 30,000 lb.
Other Allison vocational transmissions available on the T-Series include the Allison 3000 RDS close-ratio six-speed automatic transmission. It’s standard on T8500 models and is available on T7500 models. Available on all T7500 and T8500 models are Allison 3500 RDS, 3000 EVS and 3500 EVS transmissions – offered in five- and six-speed versions. T-Series customers may also equip their vehicles with an Eaton-Fuller manual transmission available in six-, nine- or 10-speed (8+2) configurations.