Hi —

Could anyone give me a couple of pointers?

First, what API or ACEA grades and viscosities should I be using for the gearbox on a TDI 100?

And second, whereabouts on the box is the filler? (It's cold outside, and I'd like to know where I'm going before I start )

Should I fill to the filler brim, or drain and refill with the correct volume?

As you may have guessed, the Haynes manual does not touch on this. Removing the gearbox, yes.

Thanks everyone,

Simon

It probably wont do any harm to renew the gearbox oil.

For the oil I would use..G 052 726 A2, you need 2 litres.

Fist check the fill plug will come undone (usually need a 14mm or a 17mm allen key to do this), sometimes they seize and if you have drained the box and find that out your stuff.

The fill plug is located at the front of the gearbox mid way up...

Now drain the diff, plug is at the back, same type of plug as the fill plug.

Also drain the main case by removing one of the support pins, T45 required for this, slide it out and keep an eye out for the o ring on it.

Then fill up until the oil runs out of the fill bung.

Edited 29 December, 200817 yr by Lummox

Cheers, Lummox — Merry Christmas!

The gearbox filler plug is a 17mm hex — Halford's do not have them, but there's a Draper hex key of that size for use with a socket driver. I paid three quid. The filler is not accessible from above: a length of plastic pipe and a funnel are recommended for negotiating a passage from topside to filler. I didn't have these to hand — fortunately, my gearbox didn't need the last third of the bottle.

The filler is not accessible from above

No, I didnt say that but as the pics were taken from underneath I guess I kinda assumed that, sorry for not pointing it out.

Some plugs are 14mm, some 17mm doesnt seem to be a lot of rhyme or reason for which one is which.

The filling tube I have is very handy, screws directly onto the genuine bottles of gearbox oil so no mess. Before I had that I used a large syringe, these are available from the likes or Draper.

No criticism intended, Lummox.

The giant syringe option occurred to me, and I might get one, not least because I'd like to take a sample of engine oil for analysis. I'll check out Draper.