Rear Diff Oil and Seals

aragorn

"Stick a V8 in it!"
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So craigs car just passed its MOT, no issues, apart from the tester said that rear driveshaft seals were leaking.

First things first we wanna make sure theres enough oil in the diff, since we dont know how long they have been leaking, what kinda oil should we be topping it up with? Any gen on whether the diff needs a special drain/fill key, or is it something off the shelf (yes i know i could just look under, but i dont have the car :p)?

secondly, we need to change the rear shaft seals, now, is this a big job? Whats involved in this one? Any specialist tools required for it?

Cheers
 
If there's just general sepage then you might be ok. Mine have been weeping since I bought the ole girl. I just keep mine topped, (which reminds me!) Now, I'm ashamed to say I've never done the job myself but the diff fluid aint that pricey and I believe is an allen bolt on the drivers side. Undo allen bolt fill to hole level. I may be wrong, definately double check this. As for the job of the diff seals, when I got a specialist (about the only I've ever had any faith in) look at replacing the seals they advised that getting into them may reveal further probelms that wouldn't need address if the diff was left intact, again, this may only be due the high mileage on mine but something else to think about.
 
Have a closer look as the "oil" may be leaking from where the CV joint bolts on to the stub axle that comes from the diff unit, I have one sitting in my garage and it would appear that the join do ooze some muck. Get yourself a Workshop manual (Elsawin) from ebay - there is a diff unit strip down, so you can see if you're brave enough! :)

Michael
 
So craigs car just passed its MOT, no issues, apart from the tester said that rear driveshaft seals were leaking.

First things first we wanna make sure theres enough oil in the diff, since we dont know how long they have been leaking, what kinda oil should we be topping it up with? Any gen on whether the diff needs a special drain/fill key, or is it something off the shelf (yes i know i could just look under, but i dont have the car :p)?

secondly, we need to change the rear shaft seals, now, is this a big job? Whats involved in this one? Any specialist tools required for it?

Cheers

http://www.audiworld.com/tech/misc.html

Just found this... may be of some help.
 
soupie did his by himself IIRC
its a large allan bolt to get on 14mm springs to mind.
I have always used redline diff/box oil
 
Seems its just 75w90 GL5 that it needs.

That thread shows the drain plugs are just hex keys, but doesnt mention the seals themselves,

I'll have a search later and see if i can find anything.

Cheers
 
Seems its just 75w90 GL5 that it needs.

That thread shows the drain plugs are just hex keys, but doesnt mention the seals themselves...

Cheers
There are no seals on the plugs just clean well and refit making shure no grit makes-it inside ! I would use the dealers stuff as i know at least 3 quattros being dammaged by using alternative "suitable" oils. I had replaced oils inside gearboxes and diffs off high mileage cars and the oil was a bit low but still within spec, no swarf or foreign particles and still a honey colour.