What the heck is my frame?

I have a mystery frankenjeep that I recently picked up. I got time this weekend, so I went out and did some measuring of its frame. It has a 2A body and I'd been told it was an FC-150 frame. Well, the actual measurements I got don't seem to fit anything I can find in a table.

The width front and rear is 29 1/4 inches. The wheelbase is 80 1/4 inches (from center of axle to center of axle). The length from front to back is 139 1/4 inches. And it has CJ5 springs front and rear (Rancho 1" lift sets, according to the numbers painted on them). It's that OAL that has me puzzled. It's too long for a CJ5, but too short for an FC-150. Any idea what it is?

 

Any signs of a shortened FC frame? Maybe it was cut.

Paul

 

I don't think it's a shortened FC frame, because the rear springs are CJ5s (46") rather than FCs (52"). I can't think of a reason someone would deliberately shorten the rear springs. And, I don't see any evidence of stretching or shortening (though I don't really know what to look for, beyond something pretty obvious). I took some photos, and should have them posted tomorrow.

 

Here are a couple photos of the frame. First the front, and then two of the rear. I don't have a good shot of the whole thing.

 

The front looks extended to me. Can you get some closer pics of it?

 

:iagree: factory front cross member been hacked and extented front. otherwise, looks like a flatty frame or early5. hard for me to tell without measuring.

 

Actually, I do have another shot of the front:


Also, note that the springs are CJ5 springs. The front ones are 39.6 inches long and the rears are 46 inches long. So if it is a lengthened CJ frame, it's probably not a 2A or 3A/B.

 

Yeh that frame is extended, looks to be extended right at the crossmember with some other frame.

 

looks like they match up better to my flatty frame.

 

Are the body mounts different between a CJ2A and a CJ5? This Jeep had a CJ2A body tub with it, though not attached. I haven't checked, but I wouldn't be surprised if the body mounts were moved to fit that 2A tub.

 

Can you get a side view of the front frame section? An FC-150 frame curves in the front of the front spring perches.

 

Hmm, the frame does curve up in front of the front axle.




I'm a bit confused, though. My copy of Jim Allen's Jeep 4x4 Performance Handbook lists the FC-150 rear springs as 52" affairs, but this frame very clearly has CJ5-sized 46" rear springs. Are FC-150 sized springs hard enough to find that someone would shorten the springs?

The book doesn't have the frame dimensions for the 150, though. The sources I've seen say the OAL on the 150 was 148" (and my frame is 139.25" long) - is it possible that the FC-150 body extends over the frame by 9 inches? That would allow the frame numbers to match up.

 

Ah - I think I solved the spring conundrum. The book lists 57-64 FC trucks, which were the ones with wider axles and other changes. If I have a 1956 FC frame, it would have come stock with CJ5 sized springs (according to this post at the Forward Forum)

 

The last picture is the cincher. That's a mount for the original Ross steering box. If it was a CJ frame, it would be behind the front axle. It's in front of the axle on the FC150. The early FC150s were built on CJ5 frames with only minimum changes. They looked really goofy with the narrow cj axles.

Enjoy...Gman