Frames: CJ7 vs CJ5

[Schvin]

Hey guys, so, I've got a '79 CJ5 . My dad took a trip a couple hours away to pick up a ton of parts for, what he was told, was a YJ. These parts included brand new frame, windshield frame, fenders, 20 gal gas tank, engine/tranny/Transmission combo, both axles and driveshafts, and quite a few more items, all for $600! Well, turns out it was a late 80's CJ7 Laredo . So I already inherited the dashboard and windshield frame. But my question is, what's the differences between a 5's frame and a 7's frame? (Other than he obviously length difference.) would I be able to cut a certain spot of the frame out and have everything else line up? My 5's frame is rotted pretty bad at the left rear spring hanger. And like I said, this frame is BRAND new. (Few years old, but new, never mounted to a vehicle). If it's decided that there's no way I can use the frame, would I be able to use the 20 gal tank??

Thanks guys. I searched but couldn't find what I was looking for.

Ben

 

[Posi]

Yes, it will work.
Cut, 10" out
The rear of the frame is wide, and then bends inward and narrows between the 2 frame body mounts
You want to cut just before the bend on the wide side, before it narrows.

 

[Schvin]

Yes, it will work.
Cut, and add 10"
The rear of the frame is wide, and then bends inward and narrows between the 2 frame body mounts
You want to cut just before the bend on the wide side, before it narrows.

So cut the 10" out of the rear/wide end?

 

[Posi]

typo, yes cut 10" out of wide end
I cut mine in the same spot but added 20" for a different project.
Measure twice cut once.

 

[Schvin]

typo, yes cut 10" out of wide end
I cut mine in the same spot but added 20" for a different project.
Measure twice cut once.

Sweet. Thank you very much! What have you done for broken body mount bolts? (I'm sure these will break on mine lol)

 

[Posi]

I'd be remiss if I didn't say welding on the frame should be done by a DOT certified welder.

Best not to cut in a straight line rather a 45 or "Z" with fish plate. Use the same plate thickness as the frame 3/16" outside 1/8" inside.

On the rusted body bolt, sawzall, cut off wheel, or nut cracker.

 

[Schvin]

I'd be remiss if I didn't say welding on the frame should be done by a DOT certified welder.

Best not to cut in a straight line rather a 45 or "Z" with fish plate. Use the same plate thickness as the frame 3/16" outside 1/8" inside.

My best friends dad has been a certified welder/welds for a living for the past 20 years. He's built several Jeep frames. And I've learned all about the 45* cuts and fish plating myself too, as I went to school for fabricating/building race cars. But I'll definitely make sure it's done properly. Thank you.

 

[Posi]

Good on you.

 

[djnineball]

Measure twice cut once.

reminds me of one of my favorite old lines...

i don't get how it can still be short. i cut it twice!

 

[daddyusmaximus]

Big score on the parts. Let us know if you can use the larger tank. V8s need larger tanks...

 

[Schvin]

Big score on the parts. Let us know if you can use the larger tank. V8s need larger tanks...

Thanks. I was pretty stoked about it. And I hope I can! My fuel gauge doesn't work, so I've been topping my little 15 gallon tank off every few days just to be safe lol.