You're using a 6400 frame as the basis of your project, and later P30 axles if I remember correctly. How have you determined your truck is built heavy enough to suit your needs?
My front axle is from 94 Chevy 3500HD, and the rear an 88 P30, both of these vehicles are rated about or a little more than a "1 ton" and they have good size disc brakes.
The frame is from a 2 ton, and I see no problems there.
The goose neck hitch I will build will help distribute the load out close to the 4 rear spring hangers and incorporate mounts for two air helper springs, whatever trailer tongue weight the axle and springs will carry should not be a problem for the frame.
Springs are made like the 52 1 ton for the front, I will have air helper springs there too so I can adjust if needed, if I have to the springs can have more leaves added.
Rear springs are like the 52 1 ton, but 1/2" additional width, they will probably be strong enough, but the air helper springs will make up the difference if not.
I am trying to build the truck just heavy enough, but not so heavy that it becomes extremely heavy itself. So far I think I am on track. An aluminum flat bed with 3/4" oak deck won't add much to the weight. Two people can easily pick up the aluminum part, the wood may weigh as much as the aluminum.
Not sure what my truck will actually carry when done, but I expect that it will handle about 6,000 lb in the bed and or a 15,000 lb trailer, probably and hopefully more, but that much should satisfy most of my needs.
Grigg
