Need some 9" education.....

Sean · March 14, 2004, 06:41:08 PM

How do you tell what you have, as far as ordering parts? The Open differential I tried to replace with my Detroit Locker has different sized Bearings, but otherwise looks pretty much the same. At first I thought it was just the bearings themselves, but the Saddles in the open Carrier are bigger too.

Here's a picture of the Locker. Is there a way to tell by looking at it? Or do I need some numbers off the case when I order the gears?

Sean · March 14, 2004, 06:47:14 PM

Heres the Bearing that i'm talking about. What do you call them? Main Bearings?

enjenjo · March 14, 2004, 08:51:43 PM

Ford changed the carrier bearing size to allow room for 31 spline axles. The change was made in 63, but they used small bearing carriers for at least 10 years after that.there are actually 4 different bearings, big ID big OD, big ID small OD, small ID small OD, and small ID big OD.

Sean · March 14, 2004, 09:15:32 PM

In the parts catalog they are showing a 1.313 pinion stem, and a 1.625 pinion stem. That appears to be the only thing that makes any difference on the Gears.

What are they calling the pinion stem? This, or the other end?

enjenjo · March 14, 2004, 10:56:39 PM

Neither. the pinion stem is the part the yoke fits on. these would be differential carrier bearings.

Sean · March 16, 2004, 11:22:40 AM

I got it out on the highway and found that it has a high pitched howl once it gets above 2400rpm in 3rd gear. Whats that mean? Too much backlash, or not enough?

Pinion depth didn't change, because I didn't mess with it. I tried to set the backlash around .015-.020, because thats where it was before I took it apart. It wasn't making any noise then.

enjenjo · March 16, 2004, 11:58:22 AM

Sounds like you have too much backlash. You should pull it back out, and reset it doing a tooth contact check with grease, or dye. I think you will find that you have a high contact pattern instead of the center to low pattern you should have. Most any good manual will have pictures of the correct pattern.

You also have to set the bearing preload on the differential bearings. The way I do it, I set the ring gear for zero backlash, and take all the play out of the bearings with the adjusters. I then tighten the adjuster opposite the ring gear two notches. this should give you the proper preload, and get you in the ballpark on backlash. I try for .004 to .009 backlash. Once that is set, check the tooth contact pattern, and you should be close.

Sean · March 16, 2004, 12:47:04 PM

I did it wrong then. I started off by mashing the ring gear tight to the pinion with preload, then tightened the other side until the bearings felt right. After I thought I had the preload right, I backed one off and tightened the other the same amount to pull the ring gear back out of the pinion until the backlash was at its original measurement.

I did check the pattern with white grease and it appeared to be close to where it was originally. Apparently not as close as I thought it was though...