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Squarebody Duramax Swaps
What is a "Squarebody"?
This term arrived about 2010 or thereabouts. The mostly younger truck enthusiasts named the 1973-1987 GM full-size pickup trucks a "Squarebody". The mostly blocky design is somewhat aptly named. My first diesel pickup was a "Squarebody", a 1982 GMC Sierra Classic, equipped with a 6.2L diesel. You can still find images of that truck in our books and other web pages here in TheDieselPage.com, which contain a lot of information about that era trucks and its original diesel engine.
However, we're also covering Duramax and Allison swaps into the Squarebody trucks, and this forum thread will become a clearinghouse for Squarebody trucks and Duramax swaps. Thanks for visiting! Feel free to post images or links to Youtube videos about your Squarebody. To begin, let's have a look at a Suburban Squarebody I found at a diesel dyno event some years ago. While not about a Duramax swap, this Suburban does contain some useful information about a diesel swap.
I was at a diesel event a few years ago, where I saw a really cool Squarebody diesel swap. I was particularly interested in the intercooler installation, as I'd heard sometime before this that it was pretty tight trying to fit a full-width intercooler in behind the grille. So, while this Suburban didn't get a Duramax, it did get a full-width intercooler!
Owner: Chris Preputin
Truck: 1986 Chevy K2500 Suburban
Engine: 1993 Dodge 5.9L 12-valve Cummins
The Spearco/Turbonetics intercooler just squeezes into the available space behind the grille.
I didn't measure the exact clearance between the bars of the grille and the face of the intercooler, so I don't know if an A/C condenser would fit, but I suspect that a way could be found to accommodate the A/C. In any event, this Suburban was a one-owner (family), recently re-painted and modified to include a Dodge Cummins, and was very well done. I'm glad the GM square-body trucks are making a comeback!
