rear dif. fluid for 85 250es

[BIG Steve]

is it ok to use 80w-90 in the rear diff of a 85 big red?

[darrel632]

You're better off with synthetic 80, but the book says you can run 80 / 90. I wouldn't do it in the cold though, drop to syntec 60 or 70 and change out every 6 months, its only 3.5 ounces or so 2 quarts will last you 4 years.

[BIG Steve]

i have some synthetic 75w-90 thati use to use in my jeep dif. and that sais for cold weather apps. would that be ok?

[TimSr]

That would be fine Steve. All it does is lube the gears in there and its not very critical. Any standard automotive gear weight oil will work fine.

[ScottZJ]

Yeah Timmy is correct. It just lubes the gears up and most average thick oil will work. Esp since you should change it almost as much as your oil if not more esp if you are in wet terrian.