Diff oil change (DIY?)

[DJones]

In truth the oil that is removed shouldn't be dirty at all, no combustion deposits and no synchroniser wear deposits should mean its clean, if its dirty something is breaking down..

I recently change the rear seals on two cars both well in excess of 100k and whilst i dont know when it was last changed (never by the state of the drain plugs!!) both were golden on removal.

Hope it helps.

Darren.

[Rikki Kitto]

Tried to do mine a while back but gave up, thought I might damage the diff case it was soooo tight

[oilman]

The Fuchs Sintopoid is spot on, very good stuff.

No oils last forever, so none are fill for life. All the manufacturers care about is getting the car through the warranty period with the minimum cost, then it's up to you if it goes wrong.

Cheers

Tim

[MattyB1]

Tim,

Your website suggest 75W85 for the rear diff - instead of 75W90? But I'm guessing the former is more than suitable for road use?

Ta.

[oilman]

Hi

Either are absolutely fine. There isn't a lot of difference at all between them, it's just that a lot of standard recommendations are towards the thin side to try to get the best fuel efficiency. As using a 75w-85 rather than 75w-90 may save about a gallon of fuel over the life of the oil, I'd go for a 75w-90 as it gives a better choice.

Cheers

Tim

[adampug11]

How much oil should my 3B rear diff take? And can anybody point out the filler hole ? Do you just fill up till it spills out the filler?

thanks in advance

[4WDrifter]

https://www.ebay.co.uk/itm/Genuine-V...72.m2749.l2649

[AndyP]

How much oil should my 3B rear diff take? And can anybody point out the filler hole ? Do you just fill up till it spills out the filler?

thanks in advance

This is the fill plug, on the RHS of the diff, drain plug is the same but on the bottom.
fill plug.jpg
Undo the filler first! Order new plugs from here, cheaper than paying £13 postage from Greece!

https://www.ebay.co.uk/itm/VW-M24x1-...AAAOSwVFlULnpG

[adampug11]

Much appreciated.I did look but it was hiding in plain sight!

cheers

[AndyP]

As stated above, they can be difficult to get out so I'd be getting some decent penetrating oil on it at least a week before doing the job!

[Bowie69]

I had to weld a great big bolt into the drain, and then crank it out.

Hard to do upside down, but then I had the diff on the bench....

[Tractor Dave]

I had to weld a great big bolt into the drain, and then crank it out.

Hard to do upside down, but then I had the diff on the bench....

I found that the best method. The welding heat does the trick

[adampug11]

Both come out easy with a bit of heat

[Bowie69]

I found that the best method. The welding heat does the trick

Yep, exactly, heat is key, though the drain was a bit mushed, so needed something else to get a good grip on as well.

Filler came out fine with the 17mm hex key.

[Bowie69]

My solution:

https://www.s2forum.com/filedata/fetch?id=2093706