[1674]

How much difference is too much? After measuring up my frame, its level in the front, level at the rear spring hangers, but the driverside frame rail has a slight curve to it, being 1/2 in lower at its worst, right in front of the front body mount. Is this too much? Currently the frame is just the front crossmemeber and two frame rails cut off about 10 inches behind the rear spring hangars.

 

[Jim_Lou]

So the driver's side frame rail has a 1/2" downward bow, right? That will mess up the body, but you can compensate with a 1/2" shim on that body mount. You might also need a thinner shim on the next body mount aft. If you don't shim the mounts you might find that hard doors don't fit right - things like that.

I don't think there would be any other adverse effects. But I would be concerned with how it got there. Is the frame rust-weakend, or was it in a crash?

You can attempt to straighten it with a timber, chains and a bottle jack. Hang the timber under the frame rail on chains. Set the bottle jack on the timber at the worst point, and put a 'softener' between the jack and frame. Then stretch a string along the frame as a reference.

Pump the jack until the frame bends about an inch, according to the string. Let the pressure off and see if there is a permanent change. Go a little farther next time and recheck until it's close to where it should be. move the jack fore and aft so that you don't get all of the bend in one place. And don't try for perfection; close is close enough.

 

[LEVE]

I'd sure want to get that curve out. It's a point of failure.... or at the very least a point that can cause a torque/twist in the future. A little heat, a reinforcing plate, a little welding and you're done.