HPI Blitz diff - what weight oil?

[Spoolio]

Hopefully will have a gear diff to put in my Blitz tonight as the ball diff it came with is pretty mullered. What is a safe thickness of oil to put in it? I've got some 1000w coming with the diff but I'm starting to think that may be no good.

Truck will be run primarily on carpet with quite a few tight twisty bits.

Cheers.

[twisty]

I used this in my Blitz gear diff,
http://www.hpiracing.co.uk/piw.php?partNo=Z157

works well.