I've read the limited number of posts here and tried to find on google of any mentioning of aftermarket lubricants (non gm part numbered) for BW rears. It seems to be a consensus that Limited slip additive is not needed for BW rears. It also seems to be agreed that 75-80 weight is the ideal weight for street use.

So out of the available aftermarket brands, which do any 9 bolt owners use or recommend for best LSD performance and longevity. I was looking at royal purple but it seems that choosing an oil that has the wrong additives is the difference between having the posi work and burning it out.

Anyone got any favorites?

 

What ever you want to use. Long as you change it when it needs to be done. I've always used semi-synthetic with a bottle of GM limited slip diff. fluid. Any of the gears I've put miles on look mint.

 

I use royal purple in my 9bolt, don't remember what weight at the moment. Been useing it for 2years now with no problems.

Conrad

 

That's what I use for my 9 bolt. Valvoline.

 

amsoil 80w90 synthetic

 

how many bottles of Royal purple were needed to fill up the rear? I may have to buy this online since i dont remember seeing it in any stores around here.

 

For the 9 bolt, I think I sued 3 bottles. But get 4 quarts just for sure.

 

2 quarts is enough....

 

Yep buy 2 quarts. You will only use 1 3/4 of it tough.

Conrad

 

check the fluid capacities in your gm or hanes manual. i bet it says 1.8 quarts. if you don't have a manual, buy one.

 

Hanes doesn't give fluid levels for the rear. Neither does the shop manual.

Funny.

 

That is my recollection too. I got two bottles of Redline Shockproof and had some left over.