View Full Version : Transmission Auto AT Final Drive 75W-90 or 80W-90?
iflights
10-20-2023, 09:03 AM
Rented a lift bay and changed all the oils out at the end of the season earlier this week. Unfortunately for the final drive, the only name brand stock locally was Royal Purple 75W-90 so I used that.
Got to thinking I might have made a mistake because of the lower viscosity and maybe plan on changing it out early next year. Hoping for some feedback on this.
JBaker4981
10-20-2023, 12:30 PM
80W-90 is the standard but I think it'll be fine
https://www.amazon.com/Lucas-10043-80W-90-Heavy-Duty/dp/B0007ZFTOA
David T
10-20-2023, 08:57 PM
80W-90 is the standard but I think it'll be fine
https://www.amazon.com/Lucas-10043-80W-90-Heavy-Duty/dp/B0007ZFTOA
I agree, you will be fine. I have seen a lot of cars VERY low on final drive gear oil and they are did fine. As important as the lube is, the final drive seems to do OK even if it is low or the stuff is not exactly correct. In the Delorean the final drive is not very highly stressed. All 140 HP is nothing compared to the 350 we put through it in a Lotus (of course in the Lotus we don't have automatics!). Remember the rule for British cars, if it stops leaking it is probably time to check the level.
iflights
10-21-2023, 09:19 AM
Thank you both. Appreciate the insight.
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