Hey guys I'm wondering what I should be putting in a 1930 Model A transmission and differential. Trans and Differential are original. but the gearbox grinds pretty bad at this point. Any recommendations?
The trans is non-synchro, it will always grind some. I think any std 80W-90 type gear oil is fine, or the 75w-140 as suggested. It is just not a real critical application.