I am gettin a differential cover and I was going to replace the fluid with some Royal Purple. My question is, do I need the posi-addative for the factory G80 locker? And how many quarts do I need to buy. Thanks, Kent.

<small>[ July 13, 2002, 02:39 AM: Message edited by: 1999stepside ]</small>

 

Yes, you need the additive. As for the ammount, the manua say to keep the level between 15 and 40mm below the fill hole. That (in my case) came to 2 quarts and 346ml out of a third and the additive of 118ml = ~2300ml or ~2.45 quarts Total.

 

According to the owners manual the factory eaton g80 gov-lock diff doesn't need any additives.

 

So that is a yes or a no on the posi addative????

 

I have a factory G80 in mine. I just changed the fluid out last weekend. I was told by the dealer to put it in. The manual for my 2001 does not call for the additive. I replaced what I had in the differential with GM 75w140 for cold weather use plus the GM locking differential additive. I am not sure why the owners manual does not call for it but it doesn't seem a bad idea to put it in. Your call but in my opinion I would say add it.

 

No additive is needed for the g80 locking differential. All you need is a good synthetic lubricant like m1 or equivalent that meets the gm specification. Additive is required on limited slip units but not on the g80.

 

i bought 3 qts of RP and use all but about half of one.