I need to change the diff fluid in both of the Subarus.
I can get a good price on M1 75W-90.
Subaru specifically recommends a 75W-90 for the rear diff, but an 80W-90 for the front one.
Does anyone have any idea why different grades of GL-5 would be recommended between the two?
Does anyone think that a 75W-90 would increase wear for the front diff if used in place of the recommended 80W-90?
I can get a good price on M1 75W-90.
Subaru specifically recommends a 75W-90 for the rear diff, but an 80W-90 for the front one.
Does anyone have any idea why different grades of GL-5 would be recommended between the two?
Does anyone think that a 75W-90 would increase wear for the front diff if used in place of the recommended 80W-90?