Recommended Hydraulic Oil Weight

I have to drain the fluid from my 1952 TO-30 to replace the PTO shaft. What do you recommend to refill it? October 20, 2014.

The recommended oil for the transmission/rear axle/hydraulic system is SAE 90 wt. mineral oil. You can purchase this oil at Tractor Supply Company stores as TSC Traveller All Mineral SAE 90 Ford Tractor Transmission Fluid, SKU # 0806600. It is sold in 2 gallon jugs and you will need approximately 6 gallons or 3 jugs.

Traveller® Ford Tractor All Mineral 90 Transmission Fluid, 2 gal. – Tractor Supply Co. Hydraulic Fluid | Brand : Traveller® | Additive Type : Premium | Size : 2 gal. | ISO Grade : 150 | Viscosity (SUS @ 100 F) : 750 | Flash Point : 455 deg. F | Pour Point : 0 deg. F | UPC : 749394806606

You will find this oil is exactly what was originally recommended by Ferguson and Massey Ferguson and is equivalent to MF 1103 oil but at a much lower price.

Thinner oils tend to leak as the seals are not designed for the use of lighter weight oils. Make sure you remove all three drain plugs to drain the oil. There are plugs at the bottom of the transmission, differential housing and hydraulic pump. There are sump areas at each location that collect water and debris. Draining the oil at all three locations makes sure all the water and debris is removed. If there is an excess amount of debris you can flush out the cases with diesel fuel or mineral spirits.