STOU/ THF

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As a small farner i use esp the STOU type of oil in my tractor.
But how good are the stou oil as an motoroil? It carries a gl4 mark so it should be having good antiwear properties for being a motoroil but maybe low on detergents- can anyone spread some light over these oils?
 
We in the states are not familiar with it, at least I am not.
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Gear lubes and THF's contain EP additives that are not nice to engine bearings and do not play well with combustion gases.
 
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STOU is a "THF" thats also used as motoroil, usually carries
API sd/cg,GL4 and some hydraulic specs.
 
Not familiar with it.

So STOU is supposed to be a combination or Universal THF/MO.

Interesting. Well I guess we have to assume STOU's additive package doesn't contain the usual P-S EP additive package.

If it's rated API SD then it most likely has a mild AW and low detergent package.

It would be interesting to post a clean oil analysis of it.
 
Perhaps you call STOU (standard tractor unversial oil) for
UTF?
Anyway its a multi use fluid for engine, trans, wetbrakes and hydraulics.
 
as far as engine goes the newer CJ oils are "better" as far as sludge and varnish aswell as soot protection.

I think the old syle STOU oils are fading due to the issues of a engine design requireing better oils than what can be made to run in all systems.

As I remember they were called Super tractor universal oils.\

Running engine, trans, hydrualic and rear axle on 1 oil puts some systems at a disadvantage as I said engine design now is requiring better oils that a 1 shot oil can deleiver
 
One remarkable thing just hit me..
A MC oil is kind of like a STOU-engine oil, gearbox and wet clutch. One is low end and the other high end!
What gives?
 
But it used in a highly loaded trans.
And normally run for short oci´s so high detergency
and soot carrying arent necessary. I think they are basically the same...but the price difference!
 
STOU as I remember, without looking is low temp tractor THF.

Tractor fluids are sometimes used in engines, but are not normally the recommended fluids as the friction modifiers reduce lubrication in low speed contact, as they are designed to grab at that point rather than lubricate.

Some brands will also use more magnesium than calcium to reduce the cost, and too much magnesium in the engine formulation is bad (per Komatsu).
 
Not intend, to hijack this thread, but my problem may be related to hijack this thread.

My LeyLand 384 Tractor is giving me hydraulic problems. I have been using cheap Hydraulic fluids from the local farm supply store. When first start working, the aux cylinders raise and lower fine. After about 1 hour getting hot, the hydraulic work real slow. I posted this on the Peatland Leyland forum which is UK based They say that we should use a STOU oil in the differential, hydraulic system which is the same. They recommend 15-40 or 20-50 motor oil! We all know the any foaming action is a no no in hydraulics. I am trying to figure out what specs to look for in choosing the right oil to use. Most folks like myself never heard of the term STOU Oil.

This could clear up some of the confusion about the STOU terminolgy!

Thank you for any response, Tom
 
Originally Posted By: MolaKule

We in the states are not familiar with it, at least I am not.
21.gif



Gear lubes and THF's contain EP additives that are not nice to engine bearings and do not play well with combustion gases.




STOU is Super Tractor Oil Universal. These fluids are common in Europe, they cover engine, transmission and hydraulics. That is not the same as UTTO which is Universal Tractor Transmission Oil which cover transmission and hydraulics. They are not interchangeable, do not use one of them where the other is specified.The main thing to be careful of when getting either one of these fluids is to use a major brand, some of the cheaper brand products are dubious to say the least, under treated additive or even no additive at all! An STOU is fine to use as long as the OEM has specified it. The engine oil performance is perfectly ok in those applications where such a product is recommended.
 
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Thanks for the response. I thinking about using the Bob Cat oil. It operates under pretty harsh conditions.
But still the LeyLand guys say use motor oil 20-50 or 15-40. It seems to me that even then that oil will get thin when it gets hot.

Tom
 
Over here, these fluids are generally called, "Universal Farm Oil" fluids.


Lubrizol also has additive packages for formulating these fluids:

STOU
 
Yes, from Afton 8801 is the STOU additive, 8703 is the UTTO product. It's important to get the terminology correct and not confuse the two fluid types.
 
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Sorry about the earlier finger problem!

I meant to say that for anyone that is interested the main Lubrizol UTTO additive is LZ 9990A.
 
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