Due to change the gearbox and diff fluid in a few weeks. I've got 1.4L of Total 80W90 for the diff, which is about 100ML short. I've also got 3L of Motul 75W90 for the gearbox, which is 200ML surplus. Should I just add 100ML of that to top off the diff or would I be best buying another liter of 80W90?

Are they the same brand ?

 

If not then no as they could have additives in the oil otherwise personally I think it should be ok.

Are they the same brand ?

 

If not then no as they could have additives in the oil otherwise personally I think it should be ok.

 

No, Total vs Motul. Hadn't thought of additives. The diff oil is cheap anyway, just annoying that I've lost such a small amount somehow.

Unlikely your gearbox or diff will drain dry which is what the fill specs will be, if your`s is UK spec with an oil cooler the amount is slightly higher, yet I have never seen a diff cooler that works, the diff temp sensor is set so high it never operates and so remains empty as its set higher than the diff.

 

Jeff