The Ford Barn

nkaminar · 05-29-2025, 05:52 AM

Here is what RYMAX says about their G5 and G4 gear oils: https://rymax-lubricants.com/updates...-gl-4-and-gl-5.

I started using G4 in my Mitchell overdrive and synchro transmission when I found small brass colored flakes in the oil I drained out during the annual change. Your choice. But for my money I will play it safe.

I buy the G4 at the local auto parts dealer. If you cannot find it there then buy it online.

I use the G5 in my differential and steering box.

One more thing: Modern gear oils are much improved over what was available in 1930. I have used 85W-140 G5 in the standard Model A gearbox and it shifts fine as long as I shift slowly or double clutch going up and double clutch going down.

05-29-2025, 05:52 AM	#15
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 6,857	Re: Mitchell over drive questions Here is what RYMAX says about their G5 and G4 gear oils: https://rymax-lubricants.com/updates...-gl-4-and-gl-5. I started using G4 in my Mitchell overdrive and synchro transmission when I found small brass colored flakes in the oil I drained out during the annual change. Your choice. But for my money I will play it safe. I buy the G4 at the local auto parts dealer. If you cannot find it there then buy it online. I use the G5 in my differential and steering box. One more thing: Modern gear oils are much improved over what was available in 1930. I have used 85W-140 G5 in the standard Model A gearbox and it shifts fine as long as I shift slowly or double clutch going up and double clutch going down. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past. Last edited by nkaminar; 05-29-2025 at 06:12 AM.