Oil & Fuel Motor Oil as the Hydraulic Oil in Power Trac

[FOURTEEN]

From my viewpoint it is much ado about nothing, an attempt to gild the lily.

PowerTrac would not have recommended engine oil if was going to HARM the system.

If someone has a headache and you don't give him an aspirin, you haven't harmed him, but you haven't helped him either!! Theoretically, if the hydraulics in a PT could last trouble free for maybe 20 years with Synthetic Hydraulic Fluid (SHF), but maybe only last 10 years with Motor Oil (MO), did PT actually HARM the PT-425 by using MO instead of SHF??



I think that Power Trac is a good responsible company, BUT, remember, ANY company is in business to make money. They do so by: (A) producing a product as economically as possible, (B) selling new products, and (C) selling replacement parts, while (D) still pleasing their owners and future customers.

(A) Power Trac, for example, may well know that SHF would be far superior to MO in hydraulics, but providing SHF in a PT-425 would cost PT about $220 more than using MO which is apparently adequate. If PT is making a $2,000? profit on each PT-425 that it sells, then PT can make an additional 11% profit just by using MO as OEM!! Of course then they can’t put MO in as OEM, but specify SHF for replacement!!

(B) By producing the PT cheaper, PT can attract more buyers. Most buyers want a machine that works OK, and seems to give good value, and a PT does both. “Gee, I don’t even have to use expensive SHF in it!”.

(C) MO will most likely get a PT through the warranty period without a repair. After the warranty period PT can make additional profit by selling replacement parts. Maybe a repair wouldn’t have been needed if SHF had been used, but who can say for sure!?!

(D) If a product makes it through the warranty period and beyond without a breakdown, most owners will be happy, and most future customers will be impressed! Maybe using SHF would double or triple the life of the PT hydraulics, but no one knows for sure, and most don’t care!!

If MO is just as good as SHF in hydraulics, why do the oil companies, which are lubrication experts, make both products? PT engineers may build a nice tractor, but that doesn’t qualify them to know what the best lubricants are! I trust PT to build a good tractor, but I rely upon the oil company to determine how to best lubricate and protect it!!


PS: I switched from MO to SHF (https://www.amsoil.com/storefront/ath.aspx) about 3 years (300 hours) ago, shortly after I got my PT-425.
Why? Because it didn’t make sense to use MO in the hydraulics, or to use SHF in the engine!
Is the PT better off? Maybe!
Was it a wise investment? Maybe!
Am I happy? YES!!
Why? Because I prefer preservation to restoration!!

 

[2deeskip]

Fourteen, right on, end of discussion!

 

[Barryh]

Hmmmm.. Something that Fourteen, and J.J. both agree on. The planets must all be in alignment. Guess I'll be going with the hydraulic oil now too.

 

[farm23]

I have read read this thread with great interest. If I could afford it I would probably go with Amsoil THF but the 1430 holds 15 gallons and I would have to take out a loan (every filter change takes about an additional 3 quarts). It seems UTF is a good compromise. My problem is finding UTF. I assume I will find it at a tractor supply store or could order on line.

 

[farm23]

After sending my last post I started looking on line for UTF. It seems UTF is 10W-20W. Is all UTF 10W-20W or are there different grades?

 

[DieselPower]

It depends. Some companies make different grades, some don't. The company I sell oil for has low temp UTF that is 5W/20, regular UTF that is 10W/20 and our UTF Red is 10W/30. We also make the John Deere specefic Special 303 Fluid which is also a 10W/20.

Most regular UTF's are 10W/20 in viscosity.

 

[MossRoad]

Then how am I going to find something compatible to the 10W40 that is in there now? If we are losing performance at high heat now, how is 20W hydraulic fluid going to improve my performance over 40W motor oil?

 

[DieselPower]

To high a viscosity or to low a viscosity fluid can cause a hydraulic system to run hot. In my opinion 10W/40 is just to thick and a 10W/30 viscosity UTF would offer the best performance. If you look at the viscosity range of the majority of hydraulic systems they run from a ISO 32 (SAE 10) to a ISO 100 (SAE 30) viscosity oil. Step up to a 40 weight and our talking ISO 150 which would be 1 1/2 to over 2 times as thick as the normal hydraulic system uses.

A good example of this is the rear axles found in heavy OTR trucks and tractors. For decades the majority of them came factory filled with a 85W/140 gear oil. It's just to thick for 90%+ of the trucks on the road. I have for years filled these rears with a 80W90 weight gear oil. What was the result? On average a temperature reduction of 50+ degrees F. By using the lower viscosity oil it induced less fluid friction/heat and greater oil flow helped to wick the heat away from the gears more efficiently. Thicker is not alway's better.

Also the UTF fluid's additive package is more suited to the reduction of friction found in a hydraulic system thereby also helping to reduce operating temps.

 

[Barryh]

To high a viscosity or to low a viscosity fluid can cause a hydraulic system to run hot. In my opinion 10W/40 is just to thick and a 10W/30 viscosity UTF would offer the best performance. If you look at the viscosity range of the majority of hydraulic systems they run from a ISO 32 (SAE 10) to a ISO 100 (SAE 30) viscosity oil. Step up to a 40 weight and our talking ISO 150 which would be 1 1/2 to over 2 times as thick as the normal hydraulic system uses.

A good example of this is the rear axles found in heavy OTR trucks and tractors. For decades the majority of them came factory filled with a 85W/140 gear oil. It's just to thick for 90%+ of the trucks on the road. I have for years filled these rears with a 80W90 weight gear oil. What was the result? On average a temperature reduction of 50+ degrees F. By using the lower viscosity oil it induced less fluid friction/heat and greater oil flow helped to wick the heat away from the gears more efficiently. Thicker is not alway's better.

Also the UTF fluid's additive package is more suited to the reduction of friction found in a hydraulic system thereby also helping to reduce operating temps.

This thread has now convinced to move to a hydraulic fluid, but it won't be until sometime this spring early summer.

I have the 10w30 motor oil that came my with my tractor right now. I have 75 hours on my PT. I get a lot of the whining and moaning just like J.J. mentions when working the PT hard.

How much wear, if any at this point would you guestimate, might be going on with these low hours? At least the viscosity is about right. I would also be curious to hear what J.J. thinks about this lower verses higher viscosity discussion.

 

[J_J]

This thread has now convinced to move to a hydraulic fluid, but it won't be until sometime this spring early summer.

I have the 10w30 motor oil that came my with my tractor right now. I have 75 hours on my PT. I get a lot of the whining and moaning just like J.J. mentions when working the PT hard.

How much wear, if any at this point would you guestimate, might be going on with these low hours? At least the viscosity is about right. I would also be curious to hear what J.J. thinks about this lower verses higher viscosity discussion.

Viscosity is independent of pressure (except at very high pressure); and
Viscosity tends to fall as temperature increases (for example, water viscosity goes from 1.79 cP to 0.28 cP in the temperature range from 0 °C to 100 °C); see temperature dependence of liquid viscosity for more details.
So what ever fluid you put in your system, the viscosity is going to change
with heat. You have noticed that the PT functions better when the fluid is about 60 to 80 degrees, and decreases as the fluid warms up.

If I were to switch to a synthetic, I would go with a single weight 40w, simply based on where I will operate the PT.

Barryh, If you are going to switch to a synthetic, you would have to get the correct fluid for your environment. I looked on the Internet for synthetic hydraulic fluid, and there are quiet a few places to visit for the info that you need. I think synthetic hydraulic fluid has all the features that one should consider when using a hyd fluid. Any fluid used in a hydraulic system is considered hydraulic fluid because it is used as a hydraulic fluid. You know of course that some fluids are better than others. I think Pt uses motor oils because it is cheap and common.

Pt should have already done these test using, say two 425's, one with synthetic in the hydraulic system, and one with motor oil, and run them a thousand hours, each one doing the same kind of work. It is just to expensive for us to be doing research to determine which fluid is the best .