Gearbox oil for S3 - latest thoughts please

[Mutley00]

I went out for my first big run on Sunday and the gear change got harder to select as the drive went on, both up and down the gears. When I got home and parked on my level drive, (reverse eventually engaged with a massive clunk!) I removed the filler plug and alot of oil came flooding out, so first thought was maybe the box had been overfilled. What oil escaped seemed reasonably clean, but I intend to change it anyway. The car has done 48K miles.

I've trawled the Forum for previous posts, but most of the chats ended years ago. The main points I picked up from the posts I read were:

1) Use Engine Oil - Mobil 1 0/40 or Castrol RS 5/40, adding Molyslip to both.
2) The gearbox synchros need a certain amount of friction to function correctly, so adding Molyslip wasn't a good idea.
3) As the exhaust runs right under the gearbox, it can heat the oil causing it to thin, so maybe some exhaust wrap maybe a good idea.

All thoughts appreciated, regards, Andrew

[phillpot]

clicky here for oil info.

Gearbox oil gets hot from doing what it does, can't see the exhaust making a difference (ten years following the S forum and not heard that one before)!
Generally gearbox's are thought to change better once the oil is hot

Is the clutch operating okay, or does it begin to "bite" as soon as pedal is off the floor?

Next you'll be asking how to drain the oil, there's no drain plug.


Pinched from another Forum, BGH are well respected Type 9 gearbox experts...........



I recently bought a new Type-9 from BGH. When I asked what oil to use, I received the following response:

"The Oil We recommend is Comma SX 75 W90 GL4. The oil is a Semi-Synthetic Multigrade gear oil to a GL4 spec. This means how slippery it is if it is too slippery I.e. GL5 the syncro doesn't properly work. If you can't find Comma use Shell, Mobile, Silkolene, or Millers please don't use other brands."

Edited by phillpot on Tuesday 7th January 15:20