[keith460]

Factory OEM bolts are 7/16-14 x 2-1/4"L but are special because the length of shank part of the bolt is 1-3/4"L so the threaded portion is not through the hinge bracket. You could purchase 7/16-14 x 3"L bolts and cut off the excess threads since the shank part of those bolts @ 1-3/4" are long enough to pass through the hinge bracket.

I was able to find 7/16 diameter S.S. Shoulder bolts like 20 years ago for mine and they work great and won't rust. Photo below is what I use.

 

[keith460]

Mcmaster-Carr is where I got those 7/16" SS Shoulder bolts a long time ago. They weren't listed in their catalog, before the internet, and they are not listed online either. I ordered them the old fashion way, called them up and they said they can get them for me and they did.
7/16" bolts are not easy to come by, by any means. I have since gone back to 3/8" bolts with the extra thread cut off since my tire carrier sports flange bushings in hinge holes now. Much smoother than the old 7/16" bolt that was steel on steel.

 

[keith460]

If you are going with the flange bushing setup, which I recommend, the holes in carrier tubing need to be drilled out slightly larger but just under 1/2". You want the bushing to be a press fit in the tubing.

There is also no need for the plastic factory washer that was used as a thrust washer since the flange bushings, when installed, will bear the load on top and bottom. The bushings when installed, will just fit between the U-shaped mounted brackets. My factory tire carrier with the weight of a 32" tire can be swung open or closed with one finger now, after it is unlatched of course. Never rattles while driving either.

 

[keith460]

It's a simple and easy fix. While I don't condone AMC/Jeep Engineering, they always looked at ways to save money and their design for the stock tire carrier was adequate for the lifespan of a typical CJ carrying a stock size tire. It was never meant to bear the weight of oversize tires and the constant jarring ride that eventually does them in.

I think the sheet metal, on the latching side of the body tub, is the first thing to go. Even though there is a backing plate for the latch receiver bracket, it is not enough. I installed a second angle bracket there, like the one on the passenger hinge side, and it has been yet another simple upgrade that greatly increases the strength of the factory tire carrier latch system. No more sheet metal tearing and makes for a solid mount.
The added bracket has a support plate underneath to displace the stress being put on it.

 

[keith460]

Would it be a good idea to put the bushings on the brackets also that way it takes up any slop the 3/8 bolts have? Or does it all pinch together when you tighten the bolts.

It all tightens down and the two "flange" bushings, four all together, in each of the square tubing does not allow the carrier to shift out of place. But you must use flange bushings.
So far, after 10 years of use with a heavy 32" spare tire mounted, it remains rattle free and no damage or tears to the sheet metal it is mounted to. Opens and closes like a brand new tire carrier.