1950s 51 Pinion Seal

[Davidcamper]

Starting on pinion seal replacement.Drag with wheels off the ground is right at 28 inch pounds. Will remove wheels and re-check. I did find the Kent Moore seal remover.

[Davidcamper]

Got the nut off. Now the hard part........retainer. Wish me luck.

[Davidcamper]

Well..........my car loves me. Retainer came out easily with a few pulls of hammer puller. No heat at all. Bearing looks good but over heated so replacing. Race looks good, no pitting. New seal should work fine.

[dogbergs]

Well done David!

I see that there can be different "cups" and ours were not alike.
Your seal is also not like the one I got.

Congratulations

/ Johan

[Jay Friedman]

Well done David!

I see that there can be different "cups" and ours were not alike.
Your seal is also not like the one I got.

Congratulations

/ Johan

My understanding is that there are 2 types of cup and seal without any pattern. Some are just one type and some are the other.  The last time I replaced this seal on my '49 I didn't know which type I had beforehand, so just ordered one of each from the supplier who allowed me to return the one I didn't use.

[Davidcamper]

Thank you Johan, you and Jay gave me the courage to try this myself.

While I was under there I found the vent hole. Clogged with mud.

There is a salvage yard about an hours drive from me that has several 51's and I crawled under them and saw first hand 2 different pinions. Why Caddy did this who knows. Same goes for vent hole..... as smart as engineers are a 1/8" vent hole? Under the brake tab? Seriously?

[The Tassie Devil(le)]

Not really a better place to put it as it is up high, and well protected by the metal flap.

I have seen lots of different ways of venting the diff, from placing a rubber hose up into the insides of the chassis, and a metallic cover that loosely fits over a small threaded tube.

Either way, the diff needs venting, to equalise the pressures as the temperature rises, to save oil seals.

Remember that these cars were never designed to go through knee-deep water, but drive along roads, even in rain.

Of all the "Road" diffs I have pulled to pieces, none have been compromised by water getting in.   Off Road diffs are a different kettle of fish, where they need to have vents that are up high, out of the way of water ingress.

Bruce.    

[Davidcamper]

All good points. Now I feel bad trashing my hero GM engineers back in the day.

[The Tassie Devil(le)]

Plus, I forgot to mention that the Automatic Transmissions also have a vent that is near the top of the transmission, and these never seem to get water going into the transmissions, no matter how much wet weather we drive through.   The FWD Eldorados have a couple of holes as vents in the axle side seals, and the Diff to Transmission case gasket.

Yes, those engineers did do a wonderful job, and us mere mortals insist on changing everything.

Bruce.

[Davidcamper]

Finally finished. Before and after.