MDchanic

So, last week, I put a Jeep Grand Cherokee steering box in my '73 Delta.

I am going to write up some information about that, but I wanted to put some miles on it first.

Meanwhile, though, I ran into an extremely important safety problem that I have to warn anyone about who does this swap, or any repairs in this area.

In order to swap in the GC steering box, you've got to use a rag joint from a transitional model, one that connects the older steering column flange to the newer steering box input shaft. You have a choice of junkyard units or several suppliers of new ones. I used a Lares 202 rag joint because I couldn't find a used one close enough to home. This warning definitely applies to the Lares unit, and may or may not apply to the Dorman or Lee units as well (it probably doesn't apply to the used factory units).

The rag joint attaches to the steering box input shaft by sliding onto the splined shaft, and then being tightened by a clamp bolt. The head of the bolt has a 7/16" 12-point pattern, and can only be installed and tightened with a 7/16" 12-point socket (a ring wrench won't fit down into the space).

When I got my rag joint, I checked it on my shaft, and noted that it matched up and slid onto the shaft perfectly. When I installed it onto the steering box, I tightened it as tight as seemed right, but noted that there was some binding between the casting of the rag joint and the thick part of the socket, requiring me to only slip the socket about halfway onto the bolt head. It seemed tight, and worked great once I had it all back together, so I didn't worry about.

Yesterday, I did some driving around (no top, no grille, no bumper, no trim ), getting a set of tires put on, a wheel alignment, some car parts, etc. The car worked great, though I'm still waiting on my shocks and hadn't yet put in proper sway bar links with my new sway bar.

When I got home, I threw down a piece of rug to lie down and put in my new top-of-the-line Raybestos / NAPA sway bar links, and reached into the car to turn the wheels to the side so I could reach the sway bar link fasteners. I gave the steering wheel a good tug (the GC steering box is a bit stiffer than the stock one was) heard a metallic "BANG," and all of a sudden the steering wheel was spinning. The U-joint seemed fine, so I pulled off the annoying plastic dust cover (earlier cars don't have this), and found that the splined fitting was spinning on the input shaft! This made me unhappy, both because I was just driving around in this car, and complete loss of steering tends to make for awkward moments, and because the Delta was blocking every other car in the driveway.

I removed the rag joint from the car. The 12-point pinch bolt seemed to be tight enough. The splines in the joint and on the input shaft were a bit dulled, but were otherwise in good shape. I tried to tighten the pinch bolt to get the joint tight on the shaft and found that I could make the bolt tight, but the joint still spun on the input shaft. I took it off and tightened it, and found that the socket I was using, which was a completely normal size, was binding between the casting of the rag joint and the head of the bold, making the bolt seem tight when it was not.
This meant that the rag joint had never been tight, and could have slipped at any time, if enough force was applied, even though the steering felt tight and had no play.

I got out my grinder and ground off about 1/16" or so of the rag joint casting where it had been touching the socket (sorry, no pictures - I was in a bit of a frenzy, and didn't know whether this would work, or how I was going to move the car out of the driveway...). If you look at it, it is obvious where to grind.

When I re-installed it, there was no interference at all between the socket and the casting, and the bolt definitely pulled in much further than it had before. I made it good and tight, and it seems to be fine.

THE MORAL OF THE STORY:
If you install a new rag joint, check it before you put it in - tighten the pinch bolt all the way down, with the socket you will be using, and if you see ANY contact between the socket and the casting, relieve that area a little bit before you put the car together.

A sudden disconnection of the steering box on a car you just fixed can be a tough one to explain to the Investigating Officer.

- Eric

Oldsguy

Wow, incredible scary, story. Kind of like this one posted yesterday about the hot 38. The only thing is, this story turned out good. Thanks for the heads-up.

Ranzan

Thanks MD I have this on order so will double check when I install

MDchanic

Some photos.
It was already ground into a curve that would accomodate the head of the pinch bolt, but it was not large enough to accomodate the socket needed to tighten the pinch bolt.


Here, you can see how much the bolt should be protruding from the other side of the clamp. If it's flush, it's to loose.



A closer view of how far the threads should protrude.





Here's a picture showing how much clearance you need for the socket - the bolt head has plenty of room.




The grinding from a different angle.


- Eric

MDchanic

This post just holds the other two pictures.

garys 68

Thanks for the heads up. Double checking mine. I think I had the same issue and ended up using a 1/4" drive socket for more clearance.

MDchanic

Yeah. Pretty sure all my ¼" sockets are hexes.

The factory spec for that bolt is 30 foot pounds, though, which is a difficult, but possible, to achieve with a ¼" drive ratchet (and might split a cheap ¼" socket).

- Eric