Model 33 combine vari-speed drive

There are 2 holes that are 90 degrees apart that have allen type plugs in them. I assume these are a check and fill for the fluid.

My question is, what type of fluid does this thing take.

I remember dad using this combine and it definitely is a vari-speed drive that was directly in line with the drive train right behind the clutch.

I want to use the vari-speed in another application.

Thank you, Dan

Oliver used different models of the Thomas Vari-Draulic drive units in the 60, fleetline and super 66's, 77's, and 88's tractors, as well as the combines that you describe. There are not many tractors around with one of the units. It was more commonly used in the combines. Other manufactures used the same units in their combines as well, but Oliver was the only one to use it it their tractors.

The correct fluid to use is automatic transmission oil Type "A". To check unit for the correct amount of fluid, turn unit until one of the holes is straight up. The other hole will then be the over flow port. Put oil in the top hole and when it starts to run out the other hole it will be 2/3 full and that is the correct level. Do not let the oil level get low as this will cause the unit to slip, fade, and surge. The grease fitting on the shifter housing should be greased with one shot of grease every 8 hours.