Hey y'all i just but a 79 cj7 for a couple hundred it has a 304 th400 transfercase is missing but ill figure that part out later. Body and frame are in fair shape. Any ways i was wanting everyones input on possible weak points to address. cant find any one thread on it so mabye we can pull cj weak points all into this one thread.All help is greatly appreciated.

Well, "CJ7 problems" is kind of vague, since there are so many differences between years, packages, and options.

But, for a 79, here are a few issues to get you started-
Tub and frame are thin and ungalvanized, so prone to rust and breakage.
Narrow-track axles.
AMC20 rear axle has 2-piece shafts and weak tubes.
Front leaf springs are 2" wide.
Gas tank is prone to rusting.

A lot of the other problems should only come up if the Jeep wasn't kept-up properly. Rebuilds, wiring, plumping, etc.

The standard 79 CJ with a 304 anbd turbo 400 transmission came with a quadratrac transfer case which is just junk. The front diff was also vacuum operated to engage the diff. The rear axle as noted above came with the two piece shafts and are weak. They can be upgraded for $300 to chromollies if you choose to keep the narow axles. I have a 77 CJ5, 79 CJ7 (for parts), and an 84 CJ7. The 77 has the narrow axles, we installed the one piece axles and 2" wheel spacers and it crawls pretty good.

i was meaning to be vauge (how ever you spell that word) i just wanted the general problem for all cjs that people have run into that way if someone was looking they could find a majority in one place. but thanx for the supplied info. The cj i just bought has a quadratrac (not installed but found it in the weeds so put in back)in it and the aformentioned crappy rear but my dana 60s will fit with minor surgery. As for a transfercase i haven't decided yet thinking about a twin sticked 300 that i picked up for 25 bucks last month.

If it was lifted alot of the times there cracked by the steering box.And the back by where the springs attach at both ends.Also behind the tranny skid.

If your addin 60s you have other issues you can address when you put them in.

went full width and coilovers and had major frame issues......plate the shit out of it

I run a 1976 CJ7 with 34's, locked, 5.0L pumping about 250HP, and shackle reversal. I have one minor crack in the frame on the passenger side where the shackle is in the front. Easy weld job, DONE.

CJ's are strong, strong as most people need them, unless they have lots of rust. Mine was a Arizona/Nevada Jeep and came with a straight rust free frame, which I give credit to not having any issues with it.

If you're going up runs at 15 MPH like a competion buggy, yes, you'll have issues, but if you're crawling (definition - slow speed) then NO, you'll have little to no issues.

PS: You will want to swap out the front shock towers regardless. http://www.in2jeep.com/fordshockmt.htm

There is a sight for refference, your better off welding them then bolting.

the D300 will not just bolt right in.
your rear pumpkin is offset.
power brakes? four way drums?
"A" style roll bar.

this is good info your given now i know where the check for craks and so will anyother newbies who happen across this thread. As far as this one im swapin frames, sellin what drive train anybody wants, and swapping in the drivetrain from a 2001 dodge ram eaisier to stretch the wheel base plus four wheel disc. this aint my first rodeo. just the first with a cj.

yeah, good idea.....im sure eventually you'll run more than "34's" with a hopped up 250 horse engine. Once you weld a crack on the frame you open the door for further cracks...all you have is a weak point from there on. Cj frames are strong for what they were built for, but im not "most people" and i do what they were not originally built for. and no.....i wasnt mobbin it like a competition buggy....frame sheared at about 5 mph. You flex wrong and a stock frame can take a dump doing 1 mph.

The front diff was also vacuum operated to engage the diff.

The only thing that's vacuum actuated in the driveline of any CJ is the emergency drive of the Qtrac transfer case.

The front diff on Qtrac equipped CJ's was engaged all the time and there are no CJ front axles that are vacuum actuated. This would be a YJ/XJ thing, not CJ.

Frames are prone to rot from the transmission skid plate back to the rear bumper.