Hi, for the V70XC model, I determined that the differentials use 75W-90 GL5 gear oil lubricant. Surprisingly, the factory manual neglected to mention this. Does the differentials require any additive?

Thanks,

Mike

 

Likely not mentioned as it is not a regular service item.

I am not aware of any special or magic potion that Volvo specified for their differentials.

 

+1, but you do have the option of using synthetic gear oils that meet the GL5 spec. I used to own a Quattro which used GL4 in the manual transmission and GL5 in the differential - I refreshed both with Redline synthetic and was amazed on the difference it made on very cold days.