UDT or Gear Oil

[lreops]

I know that it has probably been discussed before and I've been searching with no luck finding where it was posted. Question is, my manual says that you can either use UDT/Super UDT oil or SAE 80/90 weight Gear Oil in the front axle and I was wondering if there are any pro's or con's with either use. The one advantage I see is that you can combine applications between the Trans and front axle with the UDT/Super UDT needing only the one product, but is that necessarily the best or would Gear Oil in the front be a better choice? This is on a L3400DT

Thanks for your replies.

Ron

 

[Bluegill]

UDT is so thin it starts leaking at the hubs after a few hundred hours. Seems the 80/90w doesn't do this.

When I change mine I'll be using 80/90 gear oil.

 

[North Idaho Wolfman]

Think about it this way... Would you want to use 20th century lubrication technology in your 21st century tractor?
80/90 weight gear oil is an antique of a gear oil.

 

[Bluegill]

Think about it this way... Would you want to use 20th century lubrication technology in your 21st century tractor?
80/90 weight gear oil is an antique of a gear oil.

80/90 is a gear oil. UDT is hydraulic oil...

 

[lreops]

That was more along the thought process that I was thinking, Bluegill. Not to the point of eventual leakage at the hubs but the mere fact of the viscosity being so much thinner. By your comment [When I change mine I'll be using 80/90 gear oil.] it sounds like you haven't done it yet so I'm still interested in others opinions and experience.

As far as the wolfman's comment, I've yet to be convinced that some of this "New" 21st century applications are better that of the 20th century. In the 20th century, things lasted a lot longer with only minor improvements, throughout the century. Only thirteen years into this century and already many things have been changed, if not completely made obsolete. Everyone thinks that there is a better way to build a mouse trap, but the older ones still function and work the best. That's my 2¢ on that mind frame.

Again, thanks to you both for your thoughts.

Ron

 

[northcop]

I thought I had seen a maintenance video on here before saying that the 80/90 was supposed to perform poorly in colder temperatures, making systems sluggish.

 

[hodge]

Mine had UDT in the front axle, and I replaced it with UDT. 800 hours on it and no leaks.
Since Kubota intended to use UDT in it, I am comfortable continuing with it. It is thinner, and flows better when cold.

 

[kuboman]

It depends on how you use your tractor. If you use 4x4 a lot and pull hard with it I would use gear oil no matter what the temp is. If 4x4 is seldom used and you use it in winter then I would stick with UDT.

 

[Bluegill]

We're talking about the front axle here. Gears & bearings, no pumps or major oil flow.

I've had 3 Botas since 1984, the first two had 80/90. The newest L3800 has UDT in the front. I'm just over 100 hours and fixin to change it soon with gear oil...

UDT is a hydraulic oil that just happens to work in the front end. It does work excellent in HST transmissions and hydraulics, but I'm not convinced it works better than gear oil in the front axle.

 

[Toyboy]

I've got a little over 500 hr on my BX2230, but when the time comes for me to make the decision between UDT or gear oil I'll have to think hard on it. No leaks yet with UDT in it but if I do switch, I will use synthetic gear oil.

 

[Bluegill]

Kubota says to use one or the other.

So it's kind of hard to mess up here...

 

[lreops]

It depends on how you use your tractor. If you use 4x4 a lot and pull hard with it I would use gear oil no matter what the temp is. If 4x4 is seldom used and you use it in winter then I would stick with UDT.

Thank you, kuboman. Your reasoning makes sense and is a good point.

Kubota says to use one or the other.

So it's kind of hard to mess up here...

Yes, Kubota does say that either/or can be used, but like you say, one was/is used for hydraulic applications whereas Gear Oil was/is for working gears.

I was just curious of what the general consensus was.


Ron

 

[hodge]

It depends on how you use your tractor. If you use 4x4 a lot and pull hard with it I would use gear oil no matter what the temp is. If 4x4 is seldom used and you use it in winter then I would stick with UDT.

There is no gear oil in the rear ends of hydro tractors, and they pull harder than the front axle ever will. I don't have anything against gear oil, but I don't think it is sound logic to imply that UDT isn't a sufficient gear lubricant.

 

[Bulldog]

It depends on how you use your tractor. If you use 4x4 a lot and pull hard with it I would use gear oil no matter what the temp is. If 4x4 is seldom used and you use it in winter then I would stick with UDT.

I think this is very sound advise.

 

[skeets]

I look at it like this,, when I change out the hydro I change the front end and I use whats left over in the bucket for the front end. Like HD the same oil in all 3 holes, now there I have a problem. But in the Bouta same UDT or SUDT in all the drive units and M1 in the motor

 

[ipz2222]

I use full synthetic gear oil in the front. Wallmart has it in stock. I also use the same stuff in all my vehicles differentials.

 

[BXPete]

Kubota says to use one or the other.

So it's kind of hard to mess up here...

I know it's an oldish thread, but as I'm about to change my oils and have been contemplating this very issue it has been well worth a read. It does seem strange that Kubota recommend two options with such different characteristics, but the discussion here seems to address most of the pros and cons.

In my case I think I will use a gear oil as a fair bit of my work will be in 4WD on a steep(ish) block so the axle will be worked pretty well.

I think Bluegill sums it up well

Cheers,
Pete

 

[rentthis]

Keep in mind that 90w will be slower to move into the outdrive gears especially when it's cold. You should fill it and give it some time to get to where it needs to be and then check the level after a little use. I use the factory udt until it starts weeping and the switch to 90w. The weeping has always stopped. I'm in SC so temp is never a problem.

 

[Wrecker]

I have a M7040.Will any other transmission fluid brands work? It has a shuttle transmission.

 

[North Idaho Wolfman]

I use Mystik JT-5 oil it's UDT compliant, and flows great at high and low temp.
There is a lot of oils that are UDT compliant and will say so on the label.