LSD - Which oil to use?

[Guest]

I am about to fit a Sierra viscous limited diff to my SEi.

Talking to a colleague today who rallies a 4x4 Seirra - he reckons the standard EP90 fluid is not "sticky" enough for the proposed use of the diff.  He uses Silkolene Gearbox oil from a company in Telford.

Any thoughts out there as to the type of oil to use?  For the benefit of the Chesire mob - no, I don't intend to change the oil too often!

Thanks.

[ACW 191]

I run a synthetic 'LSD' rated EP90 in my LSD. bear in mind on a Westfield you want quite a 'light' setting of limited slip especially compared to a rally car.

[windy 119]

As stated many times before on this site the viscous LSD is a sealed unit so different oil viscosities have no effect on the slip characteristics of it. EP90 or EP80 oils are fine for this diff so don't be conned into buying a more expensive synthetic oil. The crownwheel and pinion lubricant is the same as for any other standard non LSD diff.

Regards

Windy

[windy 119]

Forgot to mention some other stuff!

I'd be very surprised if your friend is using viscous LSD's on a rally car as they wont last 10 minutes of this sort of abuse. He is probably using plate type LSD's which do require use of a special oil.

I am speaking from experience of destroying two viscous LSD's in my Westfield - trust me they don't last and soon revert to the characteristics of a std diff - i.e. start to spin the inside wheel in a corner. For light cars the recommended diff to use is the Quaiffe ATB version, for heavier cars plate type LSD's work better.

Regards

Windy