I have a 1968 442 that I've owned for right at two months. In that time I've been working though a bunch of issues one by one. The biggest thing that has been bothering me, which I haven't been able to correct is the steering. There is a really dead on-center feel. When I had it aligned after installing new wheels/tires, they were supposed to have inspected everything, and said it was all good. They must have just been looking at the fact that it was all painted and assumed it was all good. Because last night when I finally went under the car to begin addressing and investigating some issues underneath, I found that all my play has been coming from a missmatch in parts between the diameter of the center link stud, and the hole on the Pitman arm. The pitman arm will move quite a bit before the center link starts to move. When I took it apart, a thin piece of metal that looked like a disintegrated shim collar fell out.

So, I'm trying to figure this all out in a hurry so I can get the parts locally, and get the car back on the road. I've found that there are two different diameter studs available in the center links. Looks like a .461 and a .550. Obviously my Pitman is a .550 and my center link studs are a .461.
The power steering box is a reman Delphi unit from Flaming River. I've googled the casting numbers and can't come up with anything but it looks like an 800 series box.
The pitman arm is stamped 5693764 B which upon any google search, only pulls up for 64-67 A-body.

To fix, I was just going to buy the correct 1968 Pitman arm and the correct 1968 Center Link which from what I can tell, should be a .461 stud. My concern is that the spline count or size will be off for it to fit the steering box.
I've found the .550 center-link but If I did that, I would also have to find the correct .550 idler and replace it also.

Why are there two different sizes, and what should I do to correct this issue?

 

Pitman arm 5693764 is for a 1964-65 A-body with the 7/8" center link. You need pitman arm 5679209, which fits all 66-72 A-body with PS and the 64-65 cars with the 13/16" center link.

 

Joe,
Are the splines and shaft diameter the same between those two pitman arms?
I've ordered a new center-link and Pitman for a 68. Here's hoping it all fits.

No clue why someone would have put that pitman on my 68. But allot of stuff with this car doesn't make sense.

 

Yes, the splines on the Saginaw power steering boxes are all the same. The splines on the manual steering boxes are smaller and those pitman arms are different.

I'll bet someone swapped the steering box at one point, and just left the arm on it that was already there.

 

A few years back I had two Moog center links that were not formed correctly.
Would not fit on pitman.
My third one fit ???
Don't remember if it was a different manufacture.