Frame twist

[Mindl3ss]

After removing my bed I'm thinking my frame is a bit twisted. Looks to be about 1-1.5" lower on one side than the other, only in the rear. No buckling that I can see.

So I dropped by a frame and suspension shop to ask a few questions, but the answers didn't seem to make much sense.

Does the body/bed have to be on the frame? They said yes as they won't be able to make everything line up without it.

I figured if it's a simple twist (which I can't guarantee, but it appears to be) they could just use the factory manual spec and untwist it.

Second question, which I didn't ask because I know their answer, is it possible to untwist the frame at home? Any possibilities? I figure it would be worth the $300-400 to have it done, but considering the body isn't straight to begin with it doesn't make much sense to make it line up with the body. And I am a ways off putting it back together anyway.

[andrewmp6]

I would leave it to a pro so its done right.

[dougf]

What body issues do you have and what's your plan for future work? I ask this because if you have rusted cab supports and smashed cab and radiator support bushings it's not the best idea to have a shop basically align the body by twisting frame. I would make sure my cab supports and rad support isn't rusted, replace the bushings, then pay the pros to make it happen. I wouldn't personally mess with it. I'm only 33 but I've learned over the years sometimes you just have to buy new and pay the professionals, sometimes it's worth it.

[Mindl3ss]

The frame seems solid, just a slight twist. Nothing rotted or rusted through.

There's plenty of body work to be done.

It seems absurd that the body must be on the frame when the body just sits on the frame and the measurements from the frame to the ground are standard.

I agree to let pros handle things, I also agree that sometimes pros won't give straight answers to some random person. Seems like they're over complicating it.

[Keith Seymore]

Originally Posted by Mindl3ss

The frame seems solid, just a slight twist. Nothing rotted or rusted through.

There's plenty of body work to be done.

It seems absurd that the body must be on the frame when the body just sits on the frame and the measurements from the frame to the ground are standard.

I agree to let pros handle things, I also agree that sometimes pros won't give straight answers to some random person. Seems like they're over complicating it.

Agree.

Is the frame on a surface plate, or sitting on the suspension and wheels? It the latter, then just shim the suspension to square it back up.

The body doesn't provide any structure to a pickup, because the cab and box are separate. Not like a passenger car, where you gain some torsional rigidity from the body. It's very apparent if you ever have to opportunity to see a loose pickup frame vs a loose passenger car frame.

K

[Mindl3ss]

Originally Posted by Keith Seymore

Agree.

Is the frame on a surface plate, or sitting on the suspension and wheels? It the latter, then just shim the suspension to square it back up.

The body doesn't provide any structure to a pickup, because the cab and box are separate. Not like a passenger car, where you gain some torsional rigidity from the body. It's very apparent if you ever have to opportunity to see a loose pickup frame vs a loose passenger car frame.

K

It's on the suspension right now. I'm going to put it on jack stands and remove all the suspension so I can have it blasted and paint it.

I've heard that the suspension could just be collapsed on one side, so I figure once I get it on the stands and leveled I'll know for sure.

This image makes it seem like it would be pretty straight forward to measure and square everything up. Maybe on a plate where I can secure it and use a press or something.

[BC10]

Originally Posted by Mindl3ss

It's on the suspension right now. I'm going to put it on jack stands and remove all the suspension so I can have it blasted and paint it.

I've heard that the suspension could just be collapsed on one side, so I figure once I get it on the stands and leveled I'll know for sure.

This image makes it seem like it would be pretty straight forward to measure and square everything up. Maybe on a plate where I can secure it and use a press or something.

Is it just me, or is the second to the last cross bar sill on the right, look a little slanted in the above view on the diagram?

[t76turbo]

Originally Posted by BC10

Is it just me, or is the second to the last cross bar sill on the right, look a little slanted in the above view on the diagram?

It is. And it is on our trucks too. At least on mine. I thought something was wrong till I also saw it on other trucks in pictures of frames and things line up fine for track bar bracket etc.

[BR3W CITY]

To clarify, you aren't concerned that the frame is twisting under accel, just that at some point a situation occurred that twisted it? It didn't seem like we were talking about a 950hp front-end lifter, but wasn't sure haha.

[Mindl3ss]

Originally Posted by BR3W CITY

To clarify, you aren't concerned that the frame is twisting under accel, just that at some point a situation occurred that twisted it? It didn't seem like we were talking about a 950hp front-end lifter, but wasn't sure haha.

Yep, not there yet I don't even have an engine for it at this point, haha.

Seems like it was hit on the rear passenger corner at one point.

[BR3W CITY]

It is on my '66. I stared at it with a beer in my hand for a good half an hour before we found our old service diagrams and sure enough, its like that in the factory print.

[franken]

If the body isn't on the frame when the frame is straightened the cab/bed will still be tweaked and may not fit when you go to put it back on.

[BR3W CITY]

Originally Posted by franken

If the body isn't on the frame when the frame is straightened the cab/bed will still be tweaked and may not fit when you go to put it back on.

I think thats gonna depend on how long the body sat on a bent frame, and if the body itself sagged as a result. If you adjust your doors with a busted cab mount, they don't close right when you put a new one in....but all you have to do is readjust it.

If the cab supports themselves didn't rip/sag/rust/bow, then it should still be able to fit back on. He could go buy a brand new built chassis and toss his cab on, either way the panels will have to be refit, and the cab supports may/may not need to be shimmed.

[franken]

Originally Posted by BR3W CITY

I think thats gonna depend on how long the body sat on a bent frame, and if the body itself sagged as a result. If you adjust your doors with a busted cab mount, they don't close right when you put a new one in....but all you have to do is readjust it.

If the cab supports themselves didn't rip/sag/rust/bow, then it should still be able to fit back on. He could go buy a brand new built chassis and toss his cab on, either way the panels will have to be refit, and the cab supports may/may not need to be shimmed.

Think about it this way, the cab is basically a box. Go get a cardboard box and crush it diagonally. Now bend it back and try to make it stay square.
SOP at a bodyshop is to pull the frame with as much on the vehicle undisturbed as possible. This way the parts attached to the frame get bent back where they belong.

So the OP sold the truck because the frame might be twisted? Seems harsh.

[Mindl3ss]

Originally Posted by franken

Think about it this way, the cab is basically a box. Go get a cardboard box and crush it diagonally. Now bend it back and try to make it stay square.
SOP at a bodyshop is to pull the frame with as much on the vehicle undisturbed as possible. This way the parts attached to the frame get bent back where they belong.

So the OP sold the truck because the frame might be twisted? Seems harsh.

Nah, sold it because I'm likely moving and it would be in storage for 4+ years, along with the cost to move it to my new location. Add that on top of all the work that needs done and I figured it was best to sell it and find something more suited to my own talents (not cosmetics) when I settle down.

[BR3W CITY]

Originally Posted by franken

Think about it this way, the cab is basically a box. Go get a cardboard box and crush it diagonally. Now bend it back and try to make it stay square.
SOP at a bodyshop is to pull the frame with as much on the vehicle undisturbed as possible. This way the parts attached to the frame get bent back where they belong.

So the OP sold the truck because the frame might be twisted? Seems harsh.

I understand what your saying, but since I'm not a collision guy, I can only come at it from a builders perspective. If you dropped off an alston chassis and some donor cab, I'm not gonna ask to see the old frame....

If the cab had sagged so much that it couldn't be put on a rottiserie or something, then it was a lost cause WAY before we ever started.

[chevy_mike]

Yes, that cross member that is at an angle is to help prevent "racking" of the frame. GM engineers were smart cookies.

[Mindl3ss]

Well, as of this afternoon the twisted frame won't be my problem anyway. Truck sold and will be towed away this afternoon/evening.

Sad to see it go, but happy to have it out of the way.

Thanks for all the input everyone.

[simenad]

Could be it is just sitting higher on one side and if it is not suspension caused it could be that it was overloaded at one point and could be corrected by unriveting the cross members to let the frame drop back into position and then reattaching or replacing the crossmembers. Good time to install a rear gas tank too while the rear crossmember is out