hi

what oil to use in a 8 3/4 L S

got a bottle of valvoline vv831 with for limited slip right on front label ! 80 / 90

got a new bottle of valvoline vv831 and not limited slip on label and rear states for top off only ????????? 80 / 90

thank you !

With a cone SG use that straight up , with a clutch SG add some friction modifier . Ford dealer has the good stuff

Gus

"Ford dealer has the good stuff".......


i always thought the GM stuff was the thing to get ?
what is the real scoop, and what is the difference between the two ?
how do these compare between jeep, ram, and even say, yukon friction modifier ?

i will say one thing about the yukon stuff. my wife's 94 concorde has had a converter shudder in OD at between 1800-2000rpm for years. above or below this range, no problem. no excess junk in the pan, fluid bright cherry red, no bad smell. somewhere i read about dumping a tube of yukon stuff in would fix that. well, i did, and immediately, the shudder was gone ! i couldn't believe it ! and that was several thousand miles ago, and hasn't returned since !

The Ford additive still has the good old whale oil in it
GM is suppose to have a similar synthetic additive
I use Red Line Synthetic Super Lightweight Shockproof gear oil, the green stuff in my S/P car with a spool
I'm sure it says that it is compatible with all posi type rear ends