Club 80-90 Forums

Got a stiff one! gearbox that is! I would like to change the oil in the first instance. The van has had nine owners so who know if has ever been done!

Haynes only tell me how to top up the oil. Is there any way to completely drain it and then refill - without a massive dismantling?

Theres a large drain plug on the bottom of the gearbox, same size hex socket fitting as the filling plug (17mm).

Brilliant! thanks. Don't know why Haynes can't tell you that!

just make sure the filler nut comes off ok.before draining it..

Try to get one of these ^^^ they make filling the box MUCH easier than the old funnel and 4 yards of thin hose routine.

BTW filler bung out 1st

Ian.

Some info here as well:
https://club8090.co.uk/wiki/Ge ... drain_plug" onclick="window.open(this.href);return false;

Tony

and remember to use GL4 oil, GL5 will eat the bronzed syncromeshes

And take it for a little run beforehand to warm the oil so it runs out of the box easier.

Put a magnet in the drained oil to check to see if your gear box isn't eating it's self.
Oh and you will need 4 ltrs of oil i believe.

Oh and remember a suitable sized container to drain the old oil into...

This could go on forever!

Pepperami wrote:Put a magnet in the drained oil to check to see if your gear box isn't eating it's self.
Oh and you will need 4 ltrs of oil i believe.

No need Tony, the drain plug has a magnet built into it ... and if things is 'unwell' you get a christmas tree effect attached to it ... along with Aidan's business card

Ian

Pepperami wrote:Put a magnet in the drained oil to check to see if your gear box isn't eating it's self.
Oh and you will need 4 ltrs of oil i believe.

Is 4 ltrs correct? VW recommend only 3 lts.

Can someone please confirm that 4lts is the required amount of oil.
I've just had the oil changed and they filled it with only 3lts so I am a bit concerned.

I don't want to be charging off to France with a gearbox that is likely to eat itself.

Do I need to put in an extra litre?

From Wiki:

in the Haynes it says 3.5 litres of SAE 80

https://club8090.co.uk/wiki/Ge ... earbox_oil" onclick="window.open(this.href);return false;

vw parts catalogue does say 3 litres for the petrol 4 and five speed waterboxers, and 4 litres for the diesels !

I'd say 4 for both, and that's what I advise my re build customers; i'd rather have a little vapour/oil out of the breather than run the box dry cos that way 3rd/4th synchro failure lies. Note on the syncro box the volume is the same regardless of engine as lubrication is essential in all conditions and the syncro box is internally valved to keep oil levels consistant in each compartment regardsless of angle or attitude

Oil level is important VW check it on the service schedule but never changed it upto 90k miles last service, but note that if box is weeping oil to top up level

the reason is supposedly to make the gearchange lighter on the petrol box according to Bentley manual, that slightly baulky second gear when cold that's partly due to the shift fork and synchroniser being sat in cold oil and trying to move it out of the way, like swimming in treacle, so it gets better as oil warms and becomes less dense and more mobile

Aircooled 3.5litres and early diesel with the 091 box 4.5 litre

but there isn't 1 litre difference in the bellhousing cases and the internals are the same so why more oil in the diesel boxes ?

I'd love to meet the guys who designed the gearbox and have a good long chat with them about why the did what they did