Front Transfer Fluid

[Anonymous Poster]

Wen, I think the larger the temperature variation the more reason for the super UDT. However, I don't believe this is the only reason for the super UDT fluid. If you think of the logic of the situation you may conclude the same.

The logic being that the transfer case surrounding the gears is very close to the gears and this is a non-pressurized system. Therefore, if you get a too heavy of weight oil it may be very difficult to create a splashing effect to lubricate the gears. I really believe it is not the weight of the oil that matters in this situation, rather than the fact the the gears are fully lubricated with oil. I would rather have the gears properly lubricated with a thinner weight oil as opposed to running a heavy weight oil that is not lubricating the gears. I would also think that is why Kubota is reccommending the super UDT. We need to give these guys some credit, they have designed the very best equipment as we all know!!!

 

[MChalkley]

Jon, the lubrication techinque used in such low-rpm applications is properly considered not so much "splashing" as "dipping" or "running in". Any splashing that occurs is a by-product of the process. It's not like the Briggs & Stratton engines that lubricate the lower cylinder walls this way. The oil is carried throughout the system by being picked up by the lower part of the gear running in the oil. Therefore, the lubrication method employed is more an argument for heavier weight oil, not against it. Consider the past 4 or 5 decades of lubricant applications for differentials and you'll be closer to being on the right track for the purpose here. I think the allowance of UDT in the front axle is more of a concession to folks who don't want to have several different lubricants on hand than anything else. Take a peek inside one the next time you get a chance and I think you'll see what I mean.

Mark

 

[Anonymous Poster]

Mark, Let's look at this issue at another angle. If the super UDT fluid is good enough for our transmissions which has more gears, higher tolerances, higher speeds than why wouldn't it be good enough for the front transfer case. The logic does not make any sense why it is good for the tranny but not the front transfer axle. I would believe the transmission in my L35 is a much more critical piece of equipment than the front axle. Please tell me if my logic is flawed. Aren't these conversations great!!!! Besides, it is too late, I changed my transfer case fluid today and used super UDT.

Jon

 

[JimBinMI]

Jon,
I totally agree!/w3tcompact/icons/smile.gif After all, it is New Holland's only suggestion to put in there. I've checked my fluid in the front of my NH TC18 and it is hydraulic fluid. Bird said his B2710 came with it so Kubota is using it! But mainly it's because "I live in a Blue house with a Blue tractor", they must be right./w3tcompact/icons/cool.gif JimBinMI

 

[JimBinMI]

Mark,
You said in another post that manufacturers don't listen to customers, are not customer oriented and should have customer advisory boards. Why in the world would they care how many fluids we have to have on hand, and since they don't listen to us how would they find out this information? /w3tcompact/icons/crazy.gif New Holland, at least in my TC18 operator's manual says to use hydraulic fluid in the following places: transmission, rear axle, front fwd axle, power steering. It must be just fine to use because what manufacturer wants to recommend a lubricant that will have any kind of problem and end them up in court someday? They are the experts, after all, they built the thing they're supposed to know what to put in them...........are you just being reluctant like some people that don't choose to use synthetics just yet? /w3tcompact/icons/smile.gif Just my Blue opinion. JimBinMI

 

[MChalkley]

Joe, that's like saying that since 5w30 is what's recommended for a new Honda engine, it's what's best for a truck diesel, or even moreso, the transmission in the truck. The whole point is that the tranny on your tractor and the front axle are entirely different types of machinery - as different as the engine and the differential are in your car - and they don't take the same lubricants, either. You're right that the transmission on your L35 is a more critical piece of equipment with finer tolerances, and that's exactly why it needs the lighter weight oil. Gear oil isn't a lower quality lubricant - it's just a different lubricant for different applications. Don't get me wrong - I'm not saying that Super UDT won't work in the front axle. If Kubota says it's fine, who am I to argue? It's just that, if they say either will work, and there's such a tremendous difference between the two, I'm going to stick with the one that's typically used in this sort of application, and that's gear oil. But as I mentioned in my post in the Oils forum, I use synthetic gear oil, and get the benefit of lower cold weather viscosity to boot, so get the best of both worlds - the lower viscosity for easier flow and therefore better lubrication and the greater protection of the gear oil.

Mark

 

[MChalkley]

JimBinMI, I assume you're joking, because you're talking about New Holland and I'm talking about Kubota. If I owned a tractor that specified hydraulic oil everywhere, I'd use hydraulic oil everywhere. (But it would still be synthetic.)

What I was addressing is: The Kubota manual says you can use either in the front axle. They're giving the user the choice. Any idiot knows they're very different lubricants. So, which is better?

That's a far different issue from the one you raised. In fact, with your tractor there's no issue at all. They say use hydraulic oil and you could be creating a warranty problem to use anything else.

Mark

 

[JimBinMI]

Mark,

Yes, I know, were talking Kubota and New Holland. But seriously, do you really believe that Kubota is making a concession for its customers because they don't want to have too many fluids on hand?

I don't believe that Kubota with their worldwide reputation would recommend a fluid that wasn't equal or better than what they had previously recommended unless their engineers believed it would do an equal or superior job. Heck, for all we know the Kubota's that do recommend both fluids might be built differently?
JimBinMI

 

[MChalkley]

I don't know what their reasons are. I wish I did. All I know is that it's very unlikely that both lubricants are equally suitable. Suitable, yes. Equally, no.

They may be made differently, but if so, there's no way to tell it visually.

Mark

 

[gordon]

Mark I agree on your dipping analogy, sort of like the old waterwheel at the grainmill dipping and pouring --but where I think the heavier weight might also come into play is its holdability-I-E- to the exposed gear after long term parking. I think with the gear oil a better coating would hold onto the exposed gear rather the the hydro fluid. There by less corrosion.
Just a thought Gordon

 

[MChalkley]

All very true, Gordon. I agree completely. Less corrosion and greater lubrication.

Mark

 

[gordon]

What scare's me is that more and more manufacturers are going to the fake stuff in thier differentials./w3tcompact/icons/smile.gif
Thought you would like that---I'm still undecided on that subject--The fake juice or the dino juice that is

 

[MChalkley]

Just remember: You won't void the warranty if they don't spec it but you use it anyway. However, you will void the warranty if they do spec it and you don't use it. That should tell you something... /w3tcompact/icons/smile.gif

Mark

 

[Anonymous Poster]

Experts...manufacturers?

Another gentlemen posted that his manual states to use UDT in his 1710 NH front end, mine says 80/90 (probably a year or two older) bet we have the same front end.

Kubota says 80/90 OR UDT in the front end. I'm hoping there's different circumstances that would make each oil better but the manual sure doesn't mention it, so where are the "experts" now?

Don't get me wrong, there's a lot of brainpower in these companies, but they don't always have authority to rewrite the manuals and get out there thoughts to the public.

 

[gordon]

Ok here is a good one what spec is the UDT fluid can anyone answer that one other than Kubota sometimes they are god and they know it. Is it like Macdonalds secret sauce /w3tcompact/icons/smile.gif

 

[Anonymous Poster]

Gordon I agree with that, now how can we explain why these tractors are always built with the differential in the same pot as the transmission and they seem to hold up?

 

[Anonymous Poster]

Good question Gordon, especially considering the more dealers I contact the more different answers I get, some use Ford 134 in Kubotas, some use UDT and DO NOT use Super UDT in ANYTHING, and on and on. I've never had a new mechanical object before and received so many contradictory opinions from dealers on simple maintenance requirements!

[email]oldcarparts@mygarage.com [/email]

 

[JimBinMI]

del,

Experts...heck yes! And they better have the authority to go and rewrite the manuals. Do you know the implications that manual has and the number of customers it affects! They don't just have some yahoo rewritting manuals for something to do. At least that's an awful scary thought! /w3tcompact/icons/shocked.gif
JimBinMI

 

[W5FL]

That does not seem to be entirely true. The Kubota manuals are technically very complete. The specs on engine oil seem to have just been copied from previous versions as they are several years out of date. The Diesel spec for the Kubota oil was superceded many years ago.

Yes, it is a scary thought, but it is true that I would trust individuals on this board far above the manual recommendations. /w3tcompact/icons/smile.gif

 

[TomG]

I'm not a petro engineer, so I guess I'm using metaphors to sort out this subject. Something like thicker & stickier equals better lubrication, provided it gets to all parts. Then I realized, that I don't have any idea what the properties of hydraulic and gear oils would be at the points of gear contact. The might be the same for all I know. There certainly are huge pressures--enough to weld the surfaces of the gear faces together if overloaded.

In terms of the equivalence of hydraulic and gear oils: It's possible that they aren't equivalent, but they might give similar expected transmission lives. The idea is that the components inside a gearbox wear for different reasons and probably have different lubrication requirements. No single lubricant is likely to be ideal for all components. Perhaps, some components tend to fail when gear oil is used, and other components fail with hydraulic oil, but the expected lives are similar.

Another possibility is that the subject received little engineering attention. Maybe something fairly unrelated to lubrication (shift collars?) are expected to fail first. An assumption is that a mechanic will be into a case before a rotating component is expected to fail and will replace things as needed before failure.

Of course, these are just speculative ideas.