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R & R of Pinion Oil Seal

Musicman

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Hello to all.

I'd like to get input from anyone who knows what's involved with removing and replacing the pinion oil seal. Mine seeps lightly. It's not a really big deal as the leak is very minor. However, I wouldn't mind doing the R&R if it's possible to gain access to the seal without having to take out the entire differential. Is it possible to get to the seal for replacement by removing maybe just the drive shaft and some other minor things?

If any of you have done this job, or if you know what's involved, I'd like feedback from you about it. I'd like to do this job myself rather than paying through the nose for another mechanic to do it.

Thanks!
 
Before you do anything else, make sure the vent on the upper right part of the rear cover of the differential is free of dirt and grime. A clogged vent can cause "seeping" or worse leaks! If an illustration helps, take a look at "3 and #4 on <https://www.rimmerbros.co.uk/tr6/images/60a.gif>.
 
Andy,

Thanks for the advice. I looked at the picture. What exactly is number 3 and 4? Is the vent hole "open" or do numbers 3 and 4 close it but allow air to vent?
 
I just got the lowdown from Moss Motors. All my questions are now answered.

Thanks.
 
[ QUOTE ]
I just got the lowdown from Moss Motors. All my questions are now answered.

[/ QUOTE ]

Could you let us know what the answer was? I am sure that it will be of use to somebody!

Thanks
Alistair
 
The first thing to check is the breather hole which is on the top, right-hand side of the backside of the differential housing. If clogged, clean. Then it's not a bad idea to check the gear oil level, as too much of it can cause seepage or leaks. I was told that to access the pinion oil seal all that needs to be done is to disconnect the drive shaft at the pinion end, and then take out the nut and washer to gain access to the seal.

I'm hoping my problem will just be a clogged breather vent. I'll see later when I get home from work.
 
I would suggest being a bit less casual about changing the seal itself. The pinion bearings are assembled to a certain preload. It is wise to try and put thing back pretty much exactly where they came from. I count the threads showing above the nut I take a punch and mark the flange, the pinion itself, and the nut. When all these things line up, and the flange turns OK, then all is well.
 
Jesse,

You are most correct. It's not a job to be taken lightly. Tell me though, if I were only going as far as the seal will the pinion bearings be shifted or moved somehow, or will they stay in place once the drive shaft is removed? I was under the car after work today and it doesn't look like a job I'm going to do anytime soon. The muffler is directly in the way, and since I'm planning to replace the muffler in the near future, that will be a better time to do the pinion oil seal as well.

Thanks for your advice!
 
The pinion flange attaches to the pinion shaft.The pinion depth and bearing preload is set up when the diff is initially built. This is a critical measurement, so positioning all the parts in exactly the same place is vital. Either too loose, or too tight can cause diff failure.
 
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