GKN diff pinion nut help

[floyd12345]

Hi can any of you more knowledgeable fellows help with a couple of questions.
I have developed an oil leak from the front seal on the diff, just a couple of drips.
I had the bloody diff out a couple of weeks ago while doing a body off no problems with it then i just changed the oil now its all back together its decided to leak.
The diff performs fine no clunks or wines, i have now taken the exhaust and prop off and the pinion nut is loos just about finger tight.
How tight should this be? if i nip it up will this stop the leak, if not how hard is it to change the seal thanks.

[TJC46]

I had the diff on my S3 inspected a few years back and had both driveshaft oil seals changed. I wanted the propshaft oil seal changing as well as there was a slight leak.but i was told it did not need to be. the hub nut was slightly loose and once nipped up, the rebate in the flange face where the nut sits,was cleaned with solvent, and simplly filled with silicone before attaching the prop. Never leaked again. I was told, oil can seep down the splines/thread hence the slight leak,block off with silicone, problem cured.

[floyd12345]

thanks

[TVR Beaver]

Interesting... my later diff (are they BRG) also appears to drip the odd drip every so often.. but it don't appear to be coming from the nose end seal... Could this be the same issue?... are they configured in the same way??.. If so I'll drop the prop and have a look?...

[Simon says]

Quinny said:

Same diff in my Griff.....I had similar concerns last year, and couldn't really get a definitive answer regarding how tight the centre nut should be.......

My solution was to just take a chance, and do it by feel.... Not ideal I know, but it's been a year now and all seems fine...

My technique was to put the hand brake on and chock the wheels, then I got a good fitting socket, and an 18" breaker bar.
I then nipped the nut, until it bottomed out, and then went another half a turn..... This felt pretty tight to me, I didn't want to chance going any more, but I felt reasonably confident that it was enough...

Can't find fault with this method Quinny it worked on Ford RWD's over the years with the collapsible spacer for oil seal replacement etc,obviously a slight sense of chance but.......isn't there always apart from degreasing the threads and a smear of blue locking compound jobs a goodun,I would be inclined to say that the spacer for the bearing preload collapses in use over the years hence why the nut comes loose think when I get round to rebuilding the spare GKN I will get a solid one machined up more messing about

Edited by Simon says on Wednesday 2nd February 17:09

[spend]

Simon says said:

I would be inclined to say that the spacer for the bearing preload collapses in use over the years hence why the nut comes loose think when I get round to rebuilding the spare GKN I will get a solid one machined up more messing about

AIUI as bearings wear the assembly floats and hammers the spacer.

[dogbucket]

TVR Beaver said:

Interesting... my later diff (are they BRG) also appears to drip the odd drip every so often.. but it don't appear to be coming from the nose end seal... Could this be the same issue?... are they configured in the same way??.. If so I'll drop the prop and have a look?...

BTRs tend to blow a bit out the top vent nipple. I fitted an extension pipe to mine to raise the vent higher. Remove the osr rear wheel to get to it.