CJ-7 Shot frame and tub, Whats better to replace it with

redrussell

Active Member
I have a 79 CJ-7 and the frame is cracked in 4 places, missing a 7" chunk and was exposed to a lot of salt while it was a hunting/fishing rig on the Georgia coast. The tub is even worse off, When I removed the seats I was able to pull the seat belts from the floor by hand. Underneath everything is rotted, Replacing the entire tub is required due to rust behind the dash and the rear is badly mangled. Here is why I am still calling it a CJ-7 build though, I love the look of the CJ from the front and my front end is in great shape, I also have a nice YJ hard top and doors as well as soft top. I have a new CJ dash with custom gauges that I was going to replace the old dash with until I found the damage when I removed the old dash. I already have a cage built for a cj-7.

Here are the parts I also have and my build plans so you can keep this in mind when answering my question.
Powertrain; SBC 355tbi, SM465, NP205(Only until I get my D300 built)
Suspension; FSJ D44 8-lug front, FSJ D60 8-lug Rear, YJ Leafs (Axles are off of my J20, I have the complete truck)

I have read and been given the suggestion of getting a YJ frame and tub and just adapting my fornt fenders to the tub or building tube fenders and just using my nose. I have found several CJ-7 frames for sale but have had a very hard time finding a good CJ-7 tub. YJ frames are all over and average $100-$300 and tubs are a little more than that. I want to keep my vin plate since my home county and state(I'm military) require emissions but my jeep is old enough to be exempt. I'm looking for suggestions, I was told the YJ frame is made out of a better metal and is stronger and that the YJ tub is a little more corrosion resistent, is that true?

I want to be spring over axle so gringing and welding will need to be done to my axles. Beyond that since I am pretty much starting with a blank template instead of building from what I had I am looking for peoples thought and suggestions on what would be best for frame and body. I am rewiring whatever i go with since my engine and dash are all a custom mix.
 

redrussell

Active Member
Oh and since I am in Utah I plan to build removeable flares and flaps front and rear for while I am driving on the road since my axles will hang outside the body, I forgot to note that.
 

bryson

RME Resident Ninja
Supporting Member
Location
West Jordan
I certainly wouldn't bother trying to resurrect the CJ tub or frame - IMO, nothing on this planet is worth that headache.

I don't know about the metal composition of the YJ frame, but the design is VASTLY superior to the CJ frames. Way stronger, plus you have a better suspension design that will ride much better than the factory CJ style setup. I would 100% go with the YJ frame. Also, YJ and CJ7 tubs are nearly identical, and are often interchanged with only minor mods - the CJ front clip should be a easy swap to the YJ tub. Plus, the YJ tubs seem to hold up to rust much better than the CJ tubs - metal prep/treatment from the factory maybe?

In short, Use a YJ frame and tub, and use your CJ dash, front clip, cage...
 

redrussell

Active Member
Bryson, What about the YJ Frame is superior in your opinion? Will the spring width be the same as the FSJ? Would just save me having to move the spring pads on the Rear D60 since it is already SOA. I was worried the cage wouldn't be useable at all. All it is is a hoop with front post pillars and a 2nd hoop in the rear to protect my back seat passengers. I plan to work more on it anyways putting gussets and some more bracing I just didn't want to have to start over. Ok, then it is decided, looking for YJ parts now! Thanks guys.
 

Pile of parts

Well-Known Member
Location
South Jordan
My Jeep is based off a YJ frame and Tub. I too, like the look of a CJ and had a good hood and grill. Made tube fenders and even a flat "CJ style" dash. I had fought reinforcing and repeatedly fixing a '73 CJ 5 frame. (even weaker than your '79) and at that point, the tub was not in very good shape. Found a good YJ frame and tub for a lot less than the hassle and cost of repairing/reinforcing. You're welcome to contact me and take a look. The hardest part (not that hard) of the modification was relocating the radiator/grill support to accommodate the CJ grill. Your cage should still be usable but you will probably have to relocate spring pads on the rear and outboard the fronts.

photo 4.jpg
 

Bart

Registered User
Location
Arm Utah
What they said about the YJ frame. The only other thing you might consider is doing a TJ frame and then to a long arm linked and coiled suspension. More work, but there are a ton of suspension options out there.
 

bryson

RME Resident Ninja
Supporting Member
Location
West Jordan
The YJ frames are much stronger, wider, fully boxed, better steel (this is an assumption,) better cross member design, etc... I don't know if the FSJ axles will match up as far as the perch widths are concerned, but in the rear, at most you'd have to weld on new perches. In the front, like Jason said, you may have to outboard the spring mounts (relocate the fixed spring mount and shackle mount to the outside of the frame.) If that is the case, there are companies that sell bracket kits to do so, or it is relatively easy to do it on your own.
 

redrussell

Active Member
What they said about the YJ frame. The only other thing you might consider is doing a TJ frame and then to a long arm linked and coiled suspension. More work, but there are a ton of suspension options out there.

I have thought about coil overs but that is a new realm to me, everything I have ever owned besides my wife's suv is leaf springs. What amount of work would be required to do that and then is a YJ tub adaptable to a TJ frame? I know nothing of the TJ specs just because of its age so I never thought to research that stuff.
 

redrussell

Active Member
My Jeep is based off a YJ frame and Tub. I too, like the look of a CJ and had a good hood and grill. Made tube fenders and even a flat "CJ style" dash. I had fought reinforcing and repeatedly fixing a '73 CJ 5 frame. (even weaker than your '79) and at that point, the tub was not in very good shape. Found a good YJ frame and tub for a lot less than the hassle and cost of repairing/reinforcing. You're welcome to contact me and take a look. The hardest part (not that hard) of the modification was relocating the radiator/grill support to accommodate the CJ grill. Your cage should still be usable but you will probably have to relocate spring pads on the rear and outboard the fronts.

View attachment 97796

I would love to get together and look at what you did because if the jeep you are talking about is the picture, that is pretty much what I am wanting to end up with.
 

burke

Registered User
Location
west jordan
I just converted my cj-5 to a cj-7 with a yj tub and a throttle down kustoms cj frame. Their frames are extremely well built. A little spendy but I have had my share of cjs with rusty/cracking frames. Nice to have a solid foundation to work off of.
 
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