As above, I was about to buy Castrol b373 (for lsd) to replace the diff oil, is this suited to the diff.
Also, which oils are best for the gearbox? My box when warm is perfect but has a bit of notchiness going into first when cold. Cheers.

 

Hi

For the gearbox, go for either the Silkolene Silktran Syn 5, Motul Gear 300 or Castrol Syntrax. The Silkolene Syn 5 is ideal for the diff as well.

75w-90 Gear oil

Cheers

Tim

 

As your WRX uses viscous coupling LSD's they do not need an 'LSD oil', so go as oilman suggests.

Simon