Differential oil and seals

[NickMorgan]

Right folks, the gritting lorries were out in force last night, so the TR3 won't be venturing out for a while. One of my winter tasks will be to make the differential oil-tight again.
Last winter I discovered to my horror that the oil in the diff hadn't been changed since 1975! When I drained it, thick, dark brown oil poured out slowly. After draining overnight I refilled with EP90 oil and the diff seems to be fine - no noise at all. Now, though it leaks from the front seal, rear cover and filler plug. I think that it will be good to change the oil again and replace the rear gasket and front seal.
Any advice about how to change the front seal will be most welcome.

 

[Andrew Mace]

Nick, I'm sure you know this, but you might want to first check and make sure the vent for the differential is clean and clear. A plugged vent can cause pressure buildup and leaks that might go away almost completely when it's cleared out again.

 

[NickMorgan]

Thanks Andrew. I tried that one after I saw how much it was leaking. I was sure it would be the problem, but unfortunately it is not blocked!

 

[Brosky]

I'm on my second set of rear axle seals in the past year. Actually, these will be the third set overall. The left side seems to be fine, but the right is seeping a bit and the car hasn't even been run yet. No scoring or burrs on the flange either, so we'll see.

I did order a new seal and nyloc nut from TRF and I just noticed today that the new seal is all black and the one that I had installed two weeks ago is green and black.

Any difference? Who knows, until I talk to the guys at TRF. I just don't want any leaks. I think that these are all Chicago Rawhide seals (brand only today), so if they are still made in USA, they were always the best.

 

[prb51]

Nick,
I replaced the pinion gear seal not to long ago.
I removed the nut with an impact wrench after marking it's location relative to the pinion gear with paint dots (torqued it back to that location- not overly scientific but has worked well for a few thousand miles).
I used a spring punch to dimple each side of the old seal then gently dremel drilled a hole on either side (put grease on the seal to collect the metal shavings). Screwed in a short oversize steel screw and used a slap/slide hammer rotating sides til it worked out.
Just be careful drilling and use a short screw.
It came out smartly.
I put a Moss speedi sleeve on the pinion flange as insurance and would recommend that.
No leaks since.

 

[Jon80spit]

The leaks from the front seal and rear cover needs fixing, but the leak from the filler means it has too much oil.

 

[prb51]

or the threaded filler cap itself is buggered.

 

[Brosky]

Where did you find the listing for the Moss Speedi Seals that will fit the differential? I can't seem to find them.

Was that a direct call in request?

 

[LastDeadLast]

Paul,

It's in their catalog... give me a few and I'll get you a part number.

 

[LastDeadLast]

Moss part numbers for speedi-sleeves:

Rear Crank: 520-530 ($45.50)
Diff Pinion: 520-500 (can't remember price)

Let me know if you need any more info.

 

[Brosky]

Thanks Shannon. I've used the crank sleeve successfully, but I was hoping to find a sleeve for the axle flange to try to stop this small drip on my RR axle seal.

Oddly, there is no scoring marks on the flange. It just drips and tomorrow seal #3 will be going in. Hopefully, this will do it. It is a different seal than the others, but the same part number.

I have tried seals from Moss & TRF and both exhibit the same problem. The left side is fine.

 

[LastDeadLast]

Paul,

If you have the measurements, you can get speedi-sleeves for any application.

Here's the link to the speedi-sleeve sizing PDF.

https://www2.vsm.skf.com/Files/Brochures_in_PDF/Speedi%20Sleeve.pdf

Take care,

 

[NickMorgan]

Many thanks for the advice. I would never have thought about drilling holes and putting in screws. I will certainly give that a try. I have never heard of a speedi sleeve, either. Does this slide on the outside of the housing?

 

[Brosky]

Thanks, Shannon!!

 

[martx-5]

... I have never heard of a speedi sleeve, either. Does this slide on the outside of the housing?

It slides over the shaft (in this case the pinion shaft) where the seal rides. It 'corrects' the groove worn in the shaft by the seal. It's basically a very thin tube precisely sized for a particular application.

Here's an FAQ on Speedi-Sleeves. /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif

 

[TR3driver]

FWIW, some PTFE paste (aka pipe dope) on the filler plug will both help it seal and ease future removal. Available at Home Depot or most any plumbing supply place. If the plug itself is damaged at all, replace it. I converted all mine to hex socket plugs (which IMO are easier to work with and less apt to round off than square head plugs).

Also note that it's very important to generously lubricate the lips of the seal, plus the surface they ride on, when you install it. A quality grease will do, but I like to use assembly lube with moly.

One of my local NAPA stores was able to order the Speedi-sleeve I needed for the TR3A, but the other wasn't. Go figure. Apparently other people make them, but not as many sizes as SKF/Chicago Rawhide. The one that could came in about $10 less than Moss (not counting shipping). But even they couldn't get every possible size. I couldn't find one that fit the Stag exactly, so I used the next larger one and put some Loctite "circular parts mount" under it. Seems to work fine.