Rear crossmember: repair or replace?

[mdawg]

My '79 has some fairly booger'd/bent/warped ends on the rear crossmember (pics below), and I would like some insights on the best approach to resolve it. Here is my current thinking on options:

1. Reshape existing crossmember, using heat, clamps, hammer, etc.
   1. For heating, I would need an oxy-acetylene setup, right? (Which I have wanted for quite some time)
   2. With enough patience/trial/error would I be able to get back to a "pretty-close" shape? I have seen others mention using a porta-power, not familiar with that, though.
2. Or, replace with a new rear crossmember.
   1. Can this be done without lifting the body off of the frame?

Thanks for our thoughts, y'all.

 

[NikP]

Either approach likely depends on removal. Removal will require lifting the tub to get to the frame rivets. I doubt you'll be able to do much straightening with it in place. Once you get it removed, you can experiment with getting things straightened out to see what tools you ultimately will need or if a BFH is the tool. You might experiment with it in place trying to bend it with a big Crescent wrench or pipe wrench, but it doesn't look like you'll be able to do much in the tight spots.

 

[Hornd]

Tighten a Long Crescent wrench on it and try to straighten.
You have nothing to lose.
I have fixed many Sheet Metals with a Cresent & Hammer.

 

[pb4ugo]

You can try to straighten it in place. Hammer and something heavy for a dolly, channel locks, pry bar or anything else that might work.

Many decades ago, I was able to remove the rear crossmember and straighten it. I think i jacked up the rear of the tub a little. Once it was out i pretty much straightened it with a hammer and a flat floor. I probably used other things too. No torch. I reinstalled it and welded it in place along with the spring perch. I removed the frame angle gussets and incorporated a piece of angle iron behind it to reinforce the reciever hitch. It came out great. Later, I made a bumper and incorporated an exo skeleton. You'll be removing a crap load of rivets.

 

[3_puppies]

replacing the crossmember is time consuming, lots of rivets holding it together with the frame rails and spring mounts
don't use heat, to much collateral damage
port a power, large crescent 18-24", hammers, come a longs to a fixed object, you'll get them close, go slow and analyze what is happening while pulling

 

[mdawg]

Interesting, I'm kinda surprised how much I can shape it with a 12" crescent wrench.

As for thickness, it is 10 gauge. I'm gonna take a shot at how much I can shape it with hand tools and no heat, and we'll see how it goes. Thanks for all of your insights above!

 

[3_puppies]

you can always add an extension pipe to your 12" crescent for added leverage
it can be done without heat