Hydraulic oil for winter

Dilutexit with kerosene. That's what I do. Never had pump issues. Some also dilutes with fuel. Never tried but I have seen it

 

I don't do that type of work but dose it get better after using it a bit or due to cold it's slow no matter how much u work it

 

I've used Automatic Transmission Fluid but I don't know if it's harmful to parts and pieces in the system.
There is a special 'winter' hydraulic oil which Jack Cooper supposedly uses but I've never noticed a difference or if it's possible, they would be even slower. Double piston cylinders on a high rail still leave you standing in the cold for what seems hours.

The owner of this outfit http://www.baprod.com/ claims to have a hydraulic oil heater but I don't know cost or how well it works.
If engineers can figure out a way to keep aircraft hydraulics working at -65 it doesn't seem to be much of a leap to do it with carhaul equipment. I mentioned it to Danny Zink, Cottrell's president, for what it was worth.

 

@Heavy Hammer detailed what he uses for his pony motor hydraulics in this post.

 

@NuCar Carrier, were you by chance a former driver for NuCar (Fords) back in the '70s?...

 

If you add Kero, you have tried it. Kero is a finer grade of diesel.

In the old Anchor Motor Freight days, when it was frigid, the mechanics would go up and down the load line changing hydraulic filters and filling them with diesel before spinning them on.

It speeds up the system, not sure it does it any good though. The Anchor junk leaked anyway, so it didn't matter.

 

Auto transmission fluid with hydraulic fluid does pretty well. I have mine half n half and have for many years. Just remember ATF is a cleaner as well so if you have a seal that is a little leaky if will probably get worse if you add ATF. The aircraft hydraulic oil is no doubt probably the best but once you price it you will probably think twice, One blow line with it and you can watch the dollar signs hitting the ground!

 

A company I worked for years ago used the least expensive ATF, which I thank was type A suffix A, all year round. That running slow could cause premature pump wear due to cavitation. @GrapeApe