I need to replace a pinion bearing that is whining. As long as I'm in there, I may as well do all the rest of the bearings and seals at the same time. 228k miles is plenty, even considering it's been babied. This is one of only a few jobs I've not yet attempted, though I think I understand the concepts. FWIW, here is the best online description I've found:
http://www.richmondgear.com/01instructions.html

The depth gauge is frighteningly expensive, and is a tool for which I simply cannot see any other use. Randy's Ring and Pinion sells a "professional" ($400) and an "econo" ($200) version... and according to one of their salesman, he wishes they didn't even list the econo version in their catalog because it's a serious pain in the neck to use. His description of it sounds very similar to the tool shown in Jegs catalog for $100, which looks like a simple dial indicator with a flat mounting plate and a bunch of precision-length attachments.
http://www.jegs.com/cgi-bin/ncommerce3/ ... rmenbr=361

In searching for an instruction manual for it (or a similar type unit), here is the best I've found. Basically, it involves measuring from the flat surface of the bearing caps, and calculating an offset because the split of the caps is not likely to be directly on the centerline of the carrier bearing:
http://www.tavia.com/05001_instructions.html

In contrast, the "professional" version is strapped directly inside the carrier bearing caps, with a couple of hockey puck shaped attachments, so it knows where the centerline is automatically. And therefore it introduces a proportionately smaller margin of error, I'm sure. But I figure if I'm even within a couple thousandths, I should be able to get a reasonable contact pattern on the gear teeth... or is that foolish? Given all the horror stories I've heard about gears that start whining, even if you take it to a shop and have them do the job for you... ayi. Whining gears is not an option, in my book.

Given all the "wear pattern charts" I've seen, it seems like I ought to be able to set up a rear end perfectly by simply reading the contact pattern, but of course with a whole lot of trial and error... although I do LOVE the trick I read about, of buying an extra set of pinion bearing cups and sanding down the inside surface until it slides on and off the pinion without needing a press. Then when you've got the shims right, you take off the "checking" cups and press the real bearings on. A pretty good wear pattern chart is at the bottom of this page:
http://www.drivetrain.com/ringpinioninstal.html

Charlie, who knows a great deal more than I do about this, has cautioned me that it ain't that easy, and that I really need the depth gauge. However, since then, I read somewhere that OEM gears may not have a depth spec etched onto the pinion head, anyway... in which case the tool will be relatively (if not completely?) useless... has anyone else stumbled into this same problem? I really have no need to replace the gears, since I'm happy with the ratio, and the wear pattern is perfect.

And yea, this particular job is for a (ahem) Ford product, but the next time I do it will be for a Chrysler... and the basic technique and considerations haven't changed in 100 years, anyway. So I'm looking for any help I can get.

Thanks!

- Erik

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Lots of early Valiants and Barracudas have crossed my path.
Also a handful of other toys for variety now and then.

Erik, In your situation, reusing the same gears, and replacing the bearings, there is another option. Do not disturb the pinion gear. Remove the ring gear carrier. Measure the distance from the head of the pinion gear to any machined surface, that is convient, such as the flat areas for the bearing caps. Record this dimension. When you reinstall the pinion, set it to this same measurment. This will only work if the same gears are being reinstalled.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

I've thought of that... and it may be my best option. But considering it is almost certainly the pinion bearings that are making the growling noise (and feel rough when turned by hand), I wasn't sure the pinion would still be located in the correct spot right now, anyway. Although I cannot feel any end play in the pinion shaft (wiggling by hand) so maybe it's all right... ?

I don't know if bearing noise always equals bearing end play. Obviously it would, if the wear is taken to an extreme...

- Erik

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Lots of early Valiants and Barracudas have crossed my path.
Also a handful of other toys for variety now and then.

If you are re-using the current gear set, you can take a contact impression and a measurement as Charrlie_S discribed, then swap the bearing and see if you get lucky.
Bearings are standardized and held to pretty close tolerances so there is a good chance you will get the origional pattern back. If the pattern does not come back, use you reference mesurement to figure-out how much shim adjustment is needed and take another shot at it.
DD

I may have missed it, but what axle are we talking about? If it is a Dana, you really need a case-spreader tool to attain the proper carrier bearing preload.

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'66 Cuda 225/4spd
'66 Dart GT convertible 225/auto
'64 Dart GT 340/4spd

I have one of the econo depth setters i bought back in the late 80s. It was $125, the pro model was $225. I wish I had steped up to the pro. The parting line on the main caps aren't always the centerline of the axle so the difference has to be measured and added/subtracted in the depth measurement. Also, if the hardware is tightened down too much when checking depth, the reading can vary.
The last price I saw on a pro type model was a few years ago and it was around$300. $400 seems a little high, shop around for a lower $ if you want one.

Cecil