5-W hydraulic fluid?

[hunkydory]

My 1950-front mount 8N came with a DU-AL loader. MANY thanks to Bob for sharing the documentation with me.

Looking into replacing the fluid the manual (from 1962) says,

[b:79a83ce933]Use no heavier than No. 5-W SAE oil. If none of the above oil is available, cut back with No. 1 furnace oil to the the same weight of oil as 5-W, but we recommend 5-W.[/b:79a83ce933]

It also says,

[b:79a83ce933]Factory recommendation for this loader is 5-W SAE Oil. It would be impossible for any defects to show up in the hydraulic pump or valving in the ninety (90) day warranty period if oil heavier than 5-W is used.[/b:79a83ce933]

I've found a few sources for 5-W hydraulic oil, but they're proud of it. The implication is the system could tolerate a higher viscosity oil.

I'd appreciate your thoughts on a suitable alternative.

 

[gears]

Id run atf if its a dedicated system.

 

[TheOldHokie]

(quoted from post at 20:18:57 11/25/20) My 1950-front mount 8N came with a DU-AL loader. MANY thanks to Bob for sharing the documentation with me.

Looking into replacing the fluid the manual (from 1962) says,

Use no heavier than No. 5-W SAE oil. If none of the above oil is available, cut back with No. 1 furnace oil to the the same weight of oil as 5-W, but we recommend 5-W.[/b]

actory recommendation for this loader is 5-W SAE Oil. It would be impossible for any defects to show up in the hydraulic pump or valving in the ninety (90) day warranty period if oil heavier than 5-W is used.[/b]

Arrrg!

Thankfully today the hydraulic oil engineers have come to their senses and abandoned the use of SAE motor oil viscosity grades . That system is designed around engine oil operating temperatures in excess of 250F and meant for engine oil and only engine oil.

Hydraulic oil viscosity is specified using the more general purpose ISO grading system. That system is based around an operating temperature of 40C (104F) which is much more representative of conditions inside a hydraulic system.

You will find a wide variety of ISO hydraulic oil on the shelves. They have additive packages specifically formulated for use in mobile hydraulic systems like your loader. An AW32 hydaulic oil is going to be pretty close to whatever viscosity the DUALL engineers had in mind and a better performer than whatever they were selling at the time. If you are using the loader in sub-freezing temperatures and it is sluggish consider an AW22 grade instead.

TOH

 

[TheOldHokie]

(quoted from post at 20:18:57 11/25/20) My 1950-front mount 8N came with a DU-AL loader. MANY thanks to Bob for sharing the documentation with me.

Looking into replacing the fluid the manual (from 1962) says,

[b:440d4d1ede]Use no heavier than No. 5-W SAE oil. If none of the above oil is available, cut back with No. 1 furnace oil to the the same weight of oil as 5-W, but we recommend 5-W.[/b:440d4d1ede]

It also says,

[b:440d4d1ede]Factory recommendation for this loader is 5-W SAE Oil. It would be impossible for any defects to show up in the hydraulic pump or valving in the ninety (90) day warranty period if oil heavier than 5-W is used.[/b:440d4d1ede]

I've found a few sources for 5-W hydraulic oil, but they're proud of it. The implication is the system could tolerate a higher viscosity oil.

I'd appreciate your thoughts on a suitable alternative.

I must have inadvertently munged the BBCODE in the first reply - cell phone screens and my fingers don't play well together. The quoting is right this time.

Thankfully today the hydraulic oil engineers have come to their senses and abandoned the use of SAE motor oil viscosity grades . That system is designed around engine oil operating temperatures in excess of 250F and meant for engine oil and only engine oil.

Hydraulic oil viscosity is specified using the more general purpose ISO grading system. That system is based around an operating temperature of 40C (104F) which is much more representative of conditions inside a hydraulic system.

You will find a wide variety of ISO hydraulic oil on the shelves. They have additive packages specifically formulated for use in mobile hydraulic systems like your loader. An AW32 hydaulic oil is going to be pretty close to whatever viscosity the DUALL engineers had in mind and a better performer than whatever they were selling at the time. If you are using the loader in sub-freezing temperatures and it is sluggish consider an AW22 grade instead.

TOH

 

[hunkydory]

Thank you, TOH! I see lots of AW32 and the prices are reasonable.

Happy Thanksgiving!

 

[gears]

So ToH would atf be bad or just not as good as the aw22. Looking to learn, not challenge.

 

[TheOldHokie]

(quoted from post at 21:34:57 11/27/20) So ToH would atf be bad or just not as good as the aw22. Looking to learn, not challenge.

ATF is a hydraulic oil and the kinematic viscosity of Dexron III is about the same as an AW32 hydraulic oil. But ATF is formulated with a pricey additivev package that is specific to the needs of transmissions making it about 5X more expensive than an AW oil. AW oils are inexpensive, available in a range of viscosities, and formulated for this specific application hence my recommendation.

TOH

 

[gears]

Wish I'd known that when I built my logsplitter... Local JD dealer said they used atf on their splitters, so that's what I used. Thanks for the info, now I know for next time.

 

[TheOldHokie]

(quoted from post at 20:08:22 11/28/20) Wish I'd known that when I built my logsplitter... Local JD dealer said they used atf on their splitters, so that's what I used. Thanks for the info, now I know for next time.

The JD dealer was not wrong. ATF has a much higher viscosity index (roughly 165) than conventional AW hydraulic oil (100). That makes it a much better cold weather performer than conventional AW 32 oil. ATF is preferred by many log splitter users because it makes cold pull starts easier and improves cycle time during initial operation. Synthetic AW oils also have high VIs but that comes with a significantly higher cost so ATF becomes a cost competitive alternative.

I run my 3pt splitter off the tractor hydraulics and UTF. That is an ISO 68 oil with a VI of about 140. Electric start on the tractor and the oil is pretty well warmed up by the time the hoses get connected so it only takes a couple cycles to purge the cylinder and I am running full speed.

You have to consider the application AND operating environment if you want optimal performance.

TOH

 

[gears]

Thanks Hokie, one of these days I'll start catalogging all this info so I can quick reference.