Bambusiero
SILVER Star
FYI - Documenting what I couldn't exactly find a number for.
Just changed the front diff oil after 6 1/2 years and 35k miles of mostly low stress road use.
Measured the drain out - right at 4 quarts of nice thick dark gray/green iridescent diff soup.
I'd say it was about like a melted milk-shake, but oil slick flavored - YUMM!
4 quarts minus 8 ounces went back in, so - 80 series locking front differential oil capacity is 3.75 quarts.
My owners manual says 2.65 quarts for locking, 2.80 quarts for non-locking. Not correct I think.
Others on the forum have noted that it took more, but I couldn't find an actual number.
Just a week ago I checked the Birf grease by probing down through the fill hole with a long pipe cleaner.
The grease looked to be in good "Palladium" condition, like soft butter. No sign of liquid or dilution.
So - I take this to mean that about 8 ounces of Palladium Moly grease migrated though the seals into the diff oil over that time.
Those in the know here on the forum say this is normal migration due to the seal design and lack of other venting on the birf side of the seal.
Edit: Also - Really should have changed the diff oil out sooner just to maintain proper lubricant viscosity. Too thick is bad. Might even loose 1-2 MPG? However, a moderate amount of moly content in the oil is no problem, maybe even acts as a wear reducer.
Plus - Double check breather function.
Just changed the front diff oil after 6 1/2 years and 35k miles of mostly low stress road use.
Measured the drain out - right at 4 quarts of nice thick dark gray/green iridescent diff soup.
I'd say it was about like a melted milk-shake, but oil slick flavored - YUMM!
4 quarts minus 8 ounces went back in, so - 80 series locking front differential oil capacity is 3.75 quarts.
My owners manual says 2.65 quarts for locking, 2.80 quarts for non-locking. Not correct I think.
Others on the forum have noted that it took more, but I couldn't find an actual number.
Just a week ago I checked the Birf grease by probing down through the fill hole with a long pipe cleaner.
The grease looked to be in good "Palladium" condition, like soft butter. No sign of liquid or dilution.
So - I take this to mean that about 8 ounces of Palladium Moly grease migrated though the seals into the diff oil over that time.
Those in the know here on the forum say this is normal migration due to the seal design and lack of other venting on the birf side of the seal.
Edit: Also - Really should have changed the diff oil out sooner just to maintain proper lubricant viscosity. Too thick is bad. Might even loose 1-2 MPG? However, a moderate amount of moly content in the oil is no problem, maybe even acts as a wear reducer.
Plus - Double check breather function.
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