I've been using super UDT which is Kubota's synthetic hydro oil. I'm sold on synthetic and will use it whenever I can.
Here is a sheet I found a while back that gives a good explanation of the different hydro oils:
GETTING TO KNOW HYDRAULICS
R&O – Stand for Rust & Oxidation; also contains AntiFoam additives.
R&O is approximately a 10 weight oil with the additives
Suitable for use in applications where a premium R&O product is not
► AW – Stand for Anti-Wear; also protects against Rust & Oxidation, and
contains AntiFoam additives.
AW32 is approximately a 10 weight oil with the additives
AW46 is approximately a 15 weight oil with the additives
AW68 is approximately a 20 weight oil with the additives
AW –provides many of the advantages of premium hydraulic oil at
a moderate price. Suitable for use in applications where a Premium AW
product is not required.
All are blended with highly refined naphthenic/paraffinic base oils.
FREQUENTLY ASKED QUESTIONS
Q) What is the difference between AW32, AW46, and AW68 Hydraulic Oils?
A) The weights (10, 15 & 20) Sometimes called (ISO32, ISO46, ISO68)
Q) What is the difference between Premium AW32 and Quality AW32?
A) Quality AW32 is approximately a 1500-hour oil, whereas, Premium
AW32 has increased oxidation stabilizers making it approximately a 5000-
ECONOMY TRACTOR HYDRAULIC FLUID
TRACTOR HDYRAULIC 303 – Gives excellent results in the areas of brake
squawk, PTO clutch performance, rust protection, water sensitivity, extreme
pressure/anti-wear properties and foam suppression.
Blended from quality virgin base oils, w/high-performance
Approximately a 20 weight with the additives
Sometimes called ‘303’.
Suitable for older tractors, or where a ‘price’ fluid is desired.
Recommended as a replacement for the following manufacturers
where a tractor hydraulic fluid is recommended:
► Allis Chalmers J.I Case/David
► Ford Tractor Oliver
► International Harvester Allison
► John Deere 303 Caterpillar
► White Deutz
► Massey Ferguson
PREMIUM TRACTOR HYDRAULIC FLUID
PREMIUM TRACTOR FLUID – Gives excellent results in the areas of
transmission lubrication, differential and final drive gears. Serves as a
hydraulic medium, power steering fluid, power brake and power take-off fluid
in farm tractors.
Blended from highly refined base oils, w/superior additives.
Approximately a 10W-20 weight with the additives
Sometimes called ‘J20C’.
Recommended for most newer tractors, however can be used for
older models; also safe to use - if unsure which fluid to use. Meets the
requirements of the following manufacturers’ specified products:
► Allis Chalmers PF-821 XL Caterpillar TO2
► Sunstrand HMS-103 Oliver Type 55
► IH Hy-Tran, Spec. B-6 Vickers
► Allison C-3, C4 Kubota UDT
► Deutz HTF PF821XL White Q1722, Q1826
► Versatile Gear/Hyd. Trans. Fluid Steiger Hydraulic Trans. Fluid
► Ford Tractor M2C14B, M2C48B, M2C134B, M2C134C, M2C134D, M2C159B1, M2C159B2
► J.I Case/David Brown J1C-143, 144, 145, 185, MS-1204
► Massey Ferguson M-1110, M-1127A, M-1127-B, M1129-A, (Permatran II), M-1141 (Permatran
► IJIoIh)n Deere J20C, Quatrol, J20A (Hygrad 303), J14B, J14C, J21A, 303
FREQUENTLY ASKED QUESTIONS
Q) What is the difference between 303 Tractor Fluid and Premium Tractor Fluid?
ƒ A: The 303 Tractor Fluid is for older tractors, out of warranty, or where
the owner wants a lower cost tractor fluid. The Premium Tractor Fluid
meets the more recent requirements of tractor manufacturers.
Note: Premium Tractor Fluid can be used in older tractors, but, the 303 Tractor
Fluids should not be used in newer tractors, as it may void warranty.
Q) What is the difference between the names: Hydraulic Oil and Hydraulic Fluid?
ƒ A: No difference – just terminology.
ƒ Hydraulic Fluids work on straight hydraulic systems, such as:
Backhoes, hydraulic jacks, hydraulic vane & gear pumps, and
ƒ Tractor Fluids function as: a transmission fluid, wet brake fluid,
power steering fluid, and, hydraulic oil for the power take off.