ford 9" pinion retainer gasket

[bjde0b]

Does anybody know the part number?

[ultraranger]

I'm guessing you are talking about the large O-ring that goes between the pinion support to the 3rd member case?

http://currieenterprises2.reachlocal.ne ... px?id=1612

[Art]

There are steel shims under the pinion retainer that are used to selectively set the pinion depth with the ring gear. The thickness of this shim pack must not be changed if you want the gearset to life a long happy life.

The pinion nut is torqued to get the right amount of 'crush' on the crush sleeve. That sets the pinion bearing preload, and will need to be re-established properly as well if it gets disturbed.

[bjde0b]

my book does look like it is an o-ring. I need to "disturb" it because it is leaking. If I replace the same shims with the proper torque, will everything be okay?

[Art]

my book does look like it is an o-ring. I need to "disturb" it because it is leaking. If I replace the same shims with the proper torque, will everything be okay?

You will be ok as long as:

1.) you do not disturb the pinion nut torque setting.
2.) you do not change the shim pack thickness - remember that any dirt or rust between the shims effectively makes it "thicker". Typically the tolerance on the pinion depth setting is 0.002".

If you are 110% sure it is the O-ring that is leaking, I would pull only the 5 screws holding the pinion retainer in. With the pinion still in the retainer, pull that assembly out of the carrier and you can change the O-ring. I would clean the parts thoroughly and reassemble with a film of grease on the shims, the O-ring, and also in the bore it fits into. Grease prevents rust, makes the parts stick together nicely, and of course lubricates! Once all assembled, then clean off the excess grease and paint if desired. The torque on those 5 screws isn't critical, just torque them to spec.

I feel the chances are much higher of the pinion seal leaking than the O-ring. Not impossible, but less likely.

[ultraranger]

Depending on what your ratio is, the ring & pinion gears may be timed (non-hunting).

If it is not a timed gear set, then it would be a hunting gear set and timing would not be important.

If it is a timed (non-hunting) R&P, and if the factory timing paint markings are still visible on the teeth, you can see what two teeth of the ring gear meshes with the timed tooth of the pinion gear.

If nothing else, to be safe, if there are no paint marking on the teeth you could take a paint pen and pick a tooth on the pinion gear to mark and then mark the ring gear teeth on either side of it to get the R&P gear lined back up to that same spot, when you put the driving pinion and housing back into the 3rd member case.

Once you get it all back together, you can check your backlash with a dial indicator to be sure nothing else moved. Backlash on used gears should run .008" - .012".

Also, the O-ring does not have round shoulders. The factory O-ring has a square cut shoulder, so a common O-ring may not seal.

http://www.network54.com/Forum/74182/th ... earend+tag

[Art]

good call ultraranger, I completely overlooked the hunting / non-hunting gearsets factor...

[ultraranger]

This is an old 3.00:1 ratio 9-inch passenger car 3rd member I have. If you look at the inside edge of the ring gear, you will see the white factory paint marking on two of the teeth where this gear set was timed to one of the teeth on the driving pinion gear.

IF you have a timed gear set and IF the markings are still visible, it will look something like the markings in the photo below.