anxious

[anxious]

Would Redline 80w140 be too thick for my 1988 318i Auto?

[anxious]

Sorry guys I was thinking of the diff as an alternative to 75w90 gear oil for the differential.

Redlines website says:-

80W140

Generally used in commercial trucks which will climb long, steep grades and some racing applications where power is not critical. Generally 0.5% less efficient than 75W90. Can also be used in differentials and transmissions where excessive noise is a problem and limited-slip differentials which vibrate excessively when turning a corner. Exceeds API GL-5.

I was wondering whether it would quieten my diff backlash?

[viali8]

i think that might be too thick. i spoke to my mechanic and he said 75-90, 80-90, or a straight 90 would be fine. the bmw handbook recommends a brand name straight 90 gl-5. i just changed my diff. oil yesterday and used 80-90. it was easy to change. all u need is a 10mm hex wrench,oil and a pump to get it in there. the squirt bottle that the oil comes in will not work cause there is not that much room to work with. it takes 1.8 quarts. good luck