I have a Thomas T133 skid steer and I am due to change hydraulic oil. My manual says to use 10w30 motor oil but I was wondering if switching to something like Kubota UDT hydraulic fluid would lubricate better? Do you think hydraulic oil would prevent wear any better? I also have a backhoue attachment for it and it has the motor oil in it, would a different kind of oil be compatible? Also what do you think of running synthetic? Thanks for your help.

Check if you can use Automatic Transmision Flud fluid in the hydraulics.

My dealer said it would be OK to but he really didn't say if one was better than the other.

My lube guide shows that the recomemded lube oil is 10W30 or 20W/50 (depending on operating temp) in a SE/CD API grade. Just happens to be what they call for in the engine to.

Engine oil works but don't forget, engine oil is designed for combustion problems. In a hydraulic system there is no real need for the protection from the combustion process since it's not a engine your lubricating. A good high quality UTF (Universal Tractor Fluid) would actually be a better lubricant. It is designed to protect hydraulic systems, wet clutch systems and also lubricate the gear train system.

The hydraulic oil will provide a greater protection from cavitation caused by foam and these lubricants also have a much higher zinc anti wear additive package.

A good replacement for a system calling for a 10W/30 oil would be something like Texas Refinery Corp.'s UTF Red. Another benefit of the UTF Red is the red color makes for easy leak detection. And with their free oil analysis program the fluid life can be greatly extended.