Looking to do a frame swap

Offline246

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Currently have a 2004 Rubicon that unfortunately spent some of it formative years with a beach permit for the Jersey shore. Rear control arm attachment points are pretty well rusted thru and the tail end of the passenger frame rail is rusted out. Tub is not too bad - limited rust can be dealt with. My question is, what hidden “gotchas” might I encounter with a frame swap? Also, any great tips? Let the beatings begin....
 
I know that one you'll almost certainly encounter is a tub that is rusted on the underside.
 
Can't say much about the actual process because I had a shop do mine after I sourced the frame. Hardest part is finding a frame. Total pain in the neck. After that, be prepared to do a lot of "while you're in there" type things. Things like new gaskets / seals for the engine, possibly a new clutch if a manual, underside cleaning, etc... just make sense while you are there. I'd get a good idea of where the Jeep is right now mechanically and where you want it to be. Doing it once will save time and some money.

My tub was not very rusted out and still isn't since I don't drive in the salt. I have no rot left on the Jeep that I can find. There have been three places I've hit with a wire brush and spray bombed, but besides that everything seems sound since it didn't have rot to start with. If you have floorboards that are missing or body mounts that are failing, I would do it while the tub is off. Body mounts will be infinitely easier with the tub removed so I would check those out for sure.
 
I'm sure you plan on new body mounts. Good time to do a body lift & MML. Buy new control arms, too. Most of my bolts were seized to the sleeves in the bushings.
 
Found a frame but ... “This one had a long arm kit and now has all new Barnes lower control arm mounts and new rear uppers. “

Will this be a problem?

D5A79E0B-3372-478A-A253-F5B5930145F4.webp
 
Found a frame but ... “This one had a long arm kit and now has all new Barnes lower control arm mounts and new rear uppers. “

Will this be a problem?

View attachment 190187

If they moved the frame side control arm mounts back to stock (which is looks like they might've) then you could swap it in without changing anything. If I was going to buy a new frame I'd get one that has always been stock, but that is just me. Technically nothing stopping you from swapping that frame in assuming that the control arm mounts are all back to stock.
 
I'd take some measurements of your stock mounts, then compare them to the frame you're looking to buy. If the measurements are different, then you'll need to factor that into your total costs. If they are different, and the replacement frame is cheap enough, it might still be worth it.

In terms of other gotchas, take a careful look at the torque boxes, especially where the body mounts attach. These have a tendency to rust. Also, you're aware that there are differences between the 4 cylinder and 6 cylinder frames, as well as differences between the 97 - 02 and 03 to 06 frames?