2003 GMC T5500 BoxTruck

The 2003 GMC T5500 is a medium-duty cab-over truck, basically GMC’s version of the Isuzu F-series platform. It was built more for commercial work than comfort, but that is also why it can make a strong box truck / camper conversion platform.

Basic rundown:

The 2003 GMC T5500 is a Class 5-ish medium-duty cab-over truck. The cab-over design puts the cab above the front axle, which gives you a shorter overall truck length while still leaving a lot of room behind the cab for a box body. That is one of the big reasons these are attractive for box truck builds.

Most of these trucks were powered by an Isuzu inline-six diesel, commonly the 7.8L 6HK1-style engine family, paired with an Allison automatic transmission. The Isuzu 6H engine family was used in Isuzu medium-duty trucks and GM medium-duty trucks and was paired with Allison 2500/3000/3500 series transmissions.

A man is standing outside next to a large white truck with the words 'Protection Plants Inc.' printed on the side. The man is pointing at the truck. The sky is overcast. The ground shows some debris, rocks, and a fallen sign or frame.
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