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I have a 2000 Subaru Legacy RSK B4.

The rear diff axle seals are starting to leak. Do you know what sort of oil the diff would take and how hard do you think it would be to change the seals?

Dan.

From the "Ask Jack" archives - 23 April 2010

Numerous specialist we have contacted confirmed that the rear differential in a 2000 Legacy RSK B4 is the same as the standard Legacy.

The correct oil type is a standard and common differential oil with a viscosity of 75W-90.

BP/Castrol recommend EPX 80W-90 or the synthetic Syntrax 75W-90 while Shell have a Shell Spirax S 75W-90 or equivalent product.

Capacity is 1.2 litres.

The replacement of the seals would not appear to be that difficult.

The removal and replacement technique is critical however to ensure leaks do not reappear. Large levers and big hammers in the wrong hands can have disastrous results.

Allow around 1.5 hours per side for labour.