What is a medium-duty truck? The industry defines it as a vehicle with a Gross Vehicle Weight of 14,000 to 26,000 lbs. At 14,000 lbs., most heavy-duty one-ton trucks qualify as a medium duty vehicle. In light- and medium-duty trucks, the automatic transmission is ever increasing in popularity and numbers. So why am I talking about a clutch for a manual transmission in a shrinking market? Most of these trucks with the manual transmissions tend to be in the ownership of individuals and small fleets that do not have their own maintenance facility. This makes them a customer for a shop that has a lift and equipment to service medium-duty chassis and suspension to expand their service opportunities.

When it comes to tools, you will need a heavy-duty transmission jack. The transmission with bell housing or flywheel housing adapter can weigh more than the technician, because it is probably connected to a diesel engine. Medium-duty diesel engines are available from Cummins, Detroit Diesel, Ford, GM, Isuzu, Navistar, and other manufacturers. A Cummins ISC engine weighs 1,500-plus lbs. The transmissions are from Dana, Eaton, Getrag, New Venture Gear, and other manufacturers. A Dana Fuller 5-speed can weigh more than 300 lbs. The mating of the transmission can be similar to an automotive style with a bell housing that mounts directly to the engine or a SAE-type flywheel housing.

As for specialized training, all shops need...