About to change the gear oil in the transmission of the original 3 speed on the column transmission in a 50 Ford F1. Any recommendations on brand and weight of gear oil to use in this antique transmission? I am in Georgia so summers get to 95 and winters down to 15 or 20, and I drive year round in it.

 

I use 85/140 gear oil in the tranny and rear end.

 

Thank you sir, that was my first choice! Any additives that you add or straight gear oil? Also how often do you change yours?

 

Just straight gear oil.

I drive my truck less than 1,000 miles a year, so I haven't changed it since the first change a couple of years ago.

 

I use Valvoline 80/90. You want an oil that is safe for manual trannies (it will say so on the can, "MT" rating), safe for "yellow metals".

 

Has anyone on the forum tried redline mt-90 in their old gear boxes? I think it's a 75w-90 gl-4 gear oil.