[6cuda6]

Originally Posted by LargeMarge

re:
the 'U' bolt system to attach components to a commercial frame
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This's the standard method of attaching irregardless of component.
The 'U' bolts around the frame can attach:
* a tank body, or
* a flatbed, or
* a dump aka 'tipper', or
* a dry van.
Dimensions of a commercial truck frame are standardized, allowing a retired semi to be re-roaded as a cargo-van or dump-truck.
As the road-worthiness approaches 'kaputt', that same old truck can carry an off-highway water-tank for construction projects.
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So, 'yes', attach your dry van box using 'U' bolts.
You can buy these to your specifications at an installer of truck bodies.
Measure, take photographs, take your dimensions to the installer:
* they place the straight threaded rods in the bender, and suddenly!,
* you have four or six big honking 'U' bolts to secure your dry van box to your frame.
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For a semi-tractor, the fifth-wheel hitch is attached with a massive number of massive bolts.
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But 'U' bolts from a hardware store?
Probably on the skimpy side.
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2003, we converted a 1997 Ford CF8000 commercial truck to our concept of an ExpeditionVehicle.
2010, we converted a commercial trailer to our concept of a toy-hauler.
Each of these carried different bodies/components prior to coming home to our welcoming arms.

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See if your area has a heavy-truck dismantler aka 'wrecking-yard'.
In Eugene Oregon, we have Anderson Brothers Truck Wrecking, a walk-through museum of junked trucks and truck bodies.
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In Eugene Oregon, for those custom-bent 'U' bolts engineered to attach truck equipment to commercial frames, we have Kaiser Brake And Suspension.
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Post photographs of your progress!

Thanks for the info Sir and i will post up photo's as soon as i kick this project in high gear.