Join Date: Dec 2001
Location: Belleville, Illinois
Thanked 22 Times in 17 Posts
Welcome to the board. You've come to the right place!
I was in your shoes a few years ago, except that I also had a rusty body to deal with, although the frame was good. Or so I thought until I got the body off. That's when I found that the frame was much worse than I thought, and I would bet that yours is too. It's improbable that the body rusted away to the point where it was unusable while the frame remained sound.
There are a lot of places for the frame to rust but not be obvious. Forward of the rear axle on the inboard side there are front and rear pieces that overlap and are welded together. If the inboard piece isn't perfectly flat, it's because the frame has rusted between the two pieces. Rust is a lot bigger than the steel it comes from, so as the remaining steel gets thinner it's pushed away by the expanding rust, creating a bulge.
Look closely at the welds where the two halves were put together to form a box. Those are also overlapped. Again, rust forms between the two and spreads them apart, but there it often shows as a crack at the edge of the weld bead. Look especially closely from the back of the bend behind the rear axle, and from there aft.
Also look closely at the area where the rear spring shackle mount is bolted to the frame. Mud that gets into the rear portion of the frame tube has no way to get out since the tube is closed off by the rear cross member under the tailgate, promoting rust.
Pull the body mount bolts out and look at the frame horns where they were sandwiched between body mount biscuits. They also trap water and promote rust.
The rear three cross members are welded to the top of the frame tube with a tab that extends to the middle of the tube. That creates another water and mud trap between the tab and the frame tube. That shows up as a bulge in the tab.
And of course, the bolts that hold the skid plate up are notorious for causing problems. They screw into nuts that are swaged into the frame rails. Rust tightens the bolt in the nut while simultaneously loosening the swage. When you try to remove them the nut breaks loose from the frame, but still won't come out. Then you have to grind the head of the bolt off to drop the skid plate, and make a repair to replace the nut.
If you see these signs, you're well off to bite the bullet and plan on rebuilding or replacing the frame. Once the body is off it's not terribly difficult, and getting the body off is an afternoon's work. However, repairing the frame gets a whole lot easier if you strip it bare. Then you can stand it on end to rattle all the debris out of it. And for a few hundred you can have it hot-dip galvanized. Look at my web site to get some ideas.
It can be tempting to tackle the more obvious problems first, but there's really no point in putting time and money into a vehicle if the frame is suspect. Since everything attaches to the frame, if it's bad it can cause problems with every job you attempt.
Last edited by Jim_Lou; 10-21-2007 at 01:25 PM.