View Full Version : 3/4 ton dump - frame reinforcement ????

04-17-2007, 01:19 AM
Hi guys,
Fixing to build/install a 6'x8' dump bed on one of my military 3/4 ton 4wd Dodge trucks. My concern is that the frame should be at least "fishplated" in order to withstand the weight when dumping. I don't intend to haul very heavy loads, mostly trash ( lumber, junk, shingles, etc.), but somehow the frame just doesn't look overly substantial, by no means. I've have doubled, extended, shortened frames on heavy trucks, but never a pickup frame. Suggestions and opinions welcomed.


Gravel Rat
04-17-2007, 01:37 AM
The way to do it is build a heavy subframe for the deck to sit on so the subframe takes the stress of the hinges and the weight of the load. Then when you mount the subframe to the frame of the truck you shim it with box tubing so it follows the contour of the chassis. You can build a subframe out of 4" heavy weight structural channel.

Usually Dodges have light springs in the rear so plan on upgrading them adding overloads or timbrens or bags.

04-19-2007, 08:05 AM
I'm not sure about the earlier years but the 03+ have hydroformed frames and your not supposed to weld to them...

04-21-2007, 12:33 AM
Doesn't matter what year it is, welding to a truck frame, other than extending/shortening is a big no-no. Being as it is high tensile steel, it will harden and crack around the weld area. When frames are doubled or fishplated, you use either Grade 8 or Grade 5 bolts and I always use the existing holes rather than drilling new ones, but of course you sometimes have to drill a few extras in order to properly install the extra rail. Most of the time when a frame bends, it will do so right under the cab, hence the subframe rails will strengthen the frame directly underneath, but not past the end of them. Thanks for the replies.