Is Sta-Lube Hypoid gear oil hydraulic fluid?

[jpilk99]

Please don't laugh... I'm actually a solid driveway mechanic, but, find myself at a loss right now with the jug of Sta-Lube Hypoid SAE 80W90 "Gear Oil". Is it hydraulic fluid?

I have a Ford 1700 tractor with a nice Woods backhoe 7500 attachment and it's a little low on Hydraulic Fluid. I went into my shed and couldn't find any "Hydraulic Fluid" but found this Sta-lube Gear Oil. Can't figure out if I can use it as hydraulic fluid - or what the heck it's for.

When done chuckling, please advise. I just don't want to do the wrong thing here as I top off my hydraulic fluid for the backhoe. Thanks,

Jay

 

[RobertBrown]

No it's not

 

[Wagtail]

No it's not hydraulic fluid and shouldn't be used as such.

It is exactly what it says it is for, Gear Oil. It's used in the gearboxes of rotary tillers, 'brush hogs', finish mowers... implements that have a gear box.

My 655 tiller calls for that type of 'weight' oil for its gearbox.

 

[VTPSD]

I have a bottle of that myself in the shop, I bought it for changing out the gear oil in my old Troy Built tiller, i dont remember it being anything like hydraulic fluid, its thick like gear oil.

Could you have refilled the container with hydro fluid at some point?

 

[LD1]

How low is a little low?

If low enough to be concerned with, the average jug of gear oil ain't gonna put enough in it to be at the correct level.

Gear lube is expensive. A gallon of the stuff cost what 5 gallon of hydraulic oil will.

As to the difference....here is my take.

Oil is oil. It can be had in different weights (thickness) and different additives to make it better for different things. Gear lube is typically thicker, and loaded with extreme pressure additives to prevent the oil from breaking down under the shear of gears meshing. Engine oil has detergents and stuff to prevent sludge. Hydraulic oil has anti-foam. They all have similar properties, but some focus on key areas.

Fact is, any oil can be a hydraulic fluid. ATF is a hydraulic fluid. Alot of zero turns spec motor oil for the hydraulics.

Gear lube is a but thick though. Hydraulic oil is typically thinner so it flows well through the lines and spool valve without generating heat, and without cavitating the pump. But if one were to put a gallon of gear lube in a 6-7 gallon hydraulic system, I doubt any harm will be done and you would still have pretty thin oil.