Hey guys. im in the begining stages of my 56 build. I have a few questions on whether i should keep my frame or buy new/build? I have a longbed frame that if i keep i would shorten, My question is about the pitting in the frame. I am planning on building i nice, modern truck. (air ride, 351, manual trans(not decided) clean and modern conviences.

The frame is pitted and i am wondering if it would be more economical to just buy a new set of frame rails or to fix up these. Ill get some pics of the frame and its condition. There are no thru and thru spots it is just pitted. Also is there any way this would signifigantly weaken the frame?

thanks

 

depending on how bad it is, if your going with modern suspension, boxing in the frame will strenghten it up, i remember standing on my frame when it was not boxed and the frame sure flexes a lot, you gotta remember that was normal with the type of suspension they had in those days.

 

Personally I would just look for a donor truck that had the powertrain you wanted, don't destory the frame or scrap it though! Someone out there would be most happy to have it. If I didn't have a beefier 600 frame I would swap mine out. Lot of good donors out there, a lot of people do s-10 frame swaps because they're almost the same chassis in a lot of ways. Course you could always just use new rails, might be easier than trying to fix the old ones, plus it probably take a worry off.

 

My 2 cents would be since you want a short bed frame instead of your long bed frame, there's no sense in cutting, modifying, and doing all the suspension mod work to a badly pitted frame. You'll have some strength compromising, depending on the seriousness of the pitting, but to me, that is almost secondary to the work you'll need to do to make it look presentable, in addition to all the mod work you need to do to make it functional for your application. There's a lot of frames out there. Look for a good, solid short frame and start your project with a good, solid foundation.

 

I have a buddy with a long bed f100 frame......I think he was putting it on craigslist in Ohio.......Bill

 

But this OP already has a LB and wants a SB length frame. If the pitting is not deep and/or concentrated in an area it would not be a significant problem IMHO. Since you are planning an extensive amount of suspension mods my suggestion would be to have your frame media blasted so you can see exactly what you have, then make your decision based on your skills pocketbook and ambition. Clean metal will make modifications a lot easier and sound. Boxing the rails (and adding a K member if you want super strong) would make them strong enough to use as a bridge support. Surface pitting can be taken care of with a skim coat of surfacer putty after the frame is completed before or after priming. AFAIK there is no one making OEM style replacement frame rails for the 56. Art Morrison makes a complete tubular replacement chassis tho, a very nice piece if you can afford it.
Since the rails are basically straight and flat, you could make your own replacement rails out of rectangular tubing. Even tapering the ends is a simple job. Building a complete chasssis is best done utilizing some sort of frame table to reduce risk of warping or building out of square. It can be done on the floor, but you will need to keep any and all welds short, allow complete air cooling between each bead and constant checking for twist and square. Once you build in even a small twist or out of square, it is near impossible to correct it short of scrapping it and starting over.