Hello All,

I've just done a gearbox oil change - 6 speed manual . The big round fill and drain plugs was easy enough to find and it did look as though the oil was dirty so it was worth doing. . I want to change to differential oil as well  but I'm struggling with finding the plugs. It looks as though the diff/ transfer box is on the drivers side and the gearbox on the passenger's. I'm struggling past that! I have seen a small round plug with a hex recess, which I assume is the diff drain plug ,but I can't for the life of me see a fill plug. Because I'm not quite the idiot my wife tells me I am , I don't want to undo this without knowing where the filler is. I can't see anything much online - a lot of VW /Audi stuff looks very different to what I can see under my 2013 4x4 3T. Is there a guide anywhere?

Cheers.

I'm pretty certain the front diff and gearbox are in the same casing and share oil. Not 100% sure about the transfer case. I'd suggest you get hold of the service manual: https://erwin.skoda-auto.cz/erwin/showHome.do

Hi ,

Thanks. I must admit that's what i thought to start with but then I saw a post that said - DSG or manual- that the transfer box had a seperate oil supply. 

Thanks again for the link to a manual. I must admit I fumble about a bit without there being a Haynes manual for the Superb .

On 29/06/2023 at 09:50, graeme1177 said:

Hi ,

Thanks. I must admit that's what i thought to start with but then I saw a post that said - DSG or manual- that the transfer box had a seperate oil supply. 

Thanks again for the link to a manual. I must admit I fumble about a bit without there being a Haynes manual for the Superb .

You're right the transfer box has its own oil supply and doesn't share any oil with the gearbox or front differential.

It also has its own oil specification detailed in parts manuals as part number G052145S2.

https://www.lllparts.co.uk/product/G052145S2/axle-oil-br-filling-quantity

A tips for those who do this job. Be sure to fill in 2 stages. It is supposed to be 850-900ml in there, but all will not come out during drain. So at least put in 650-750ml. First fill until drips out of fill hole. Probably only 5-600ml will be initial. Then start engine and put in 1.gear let it reach some temp. If on lifter, just let it run. Or take it for a spin. Then top off again. You will probably be able to get another 100-150ml in now. It doesn't do any harm to overfill a bit, since it is a drain hole on top of the diff/transfer box that will shoot out exessive oil if overfilled when warm.

A tip for those of you who replaces dmf or bevelbox, when subframe is already down. You can actually fill bevelbox as usual, but also top off by filling through the mentioned vent hole on top. You will be able to get 800-850ml inside the transferbox without driving it then. The vent hole is on top of the pinion gear ish.

Here is a pic of the vent hole that can be used to top off the bevelbox/angle gear/transfer box (same part different names) if subframe is down.

It is not possible to reach that vent hole when subframe is mounted. Not at least with my hands. I used a small tube connected to a 200ml big syringe