Buying a used L3430 GST changing transmission fluiid

[rScotty]

The Kubota oil is a plus for powershift tractors and hydro's! There are different oils available but they do not give the same performance!

Well, lets look into it a bit.
The PowerShift/GST transmissions work on a comlpletely different principle than the Hydrostats. The parts are not even roughly comperable. The PowerShift/GlideShift/GST is a mechanical geared transmission with lots of mechanical contact and internal friction clutches.... It basically looks like every old stick shift automotive tranny since the 1920 except that there are far more clutches and they are internal to the transmission instead of being somewhere dry like in a traditional bell housing.

While the other kind of tranny - the hydrostaic transmission - is basically a set of fluid-coupled pumps with impeller fans running in fluid that never touch one another and pass the input/output power back and forth by means of their fluid coupling. To us old mechanics the inside of HST looks like some sort of cross between a jet turbine and an alien massage machine. The only mechanical part inside most HST is the slider pin that sets the wobble plate angle - and some makes don't even have that.
So if the way these common transmissions work is so different....and the kind of friction they deal with is way more different....then why in the world do we keep insisting that an oil that is great for one kind is anything more than passable for the other?? Are we just buying into advertising hype?
rScotty

 

[Fallon]

It could be hype. But if you search these forums for people with rough shifting you'll find a lot & find they all pretty much end when they go back to SUDT2 or the other one. Same for whining & other poor behavior with HSTs.

SUDT2 has advantages at lower tempatures over the other one. I live in Colorado so never paid attention to the other one. Think it's SUDT or UDT2. Pretty sure there was one between UDT & SUDT2.

 

[Spanner]

I am in the process of buying a used Kubot L3430 with around 2100 hrs on it. The owner says he never changed the transmission fluid in it. The manual says to change every 400 hrs and I am wondering if it needs to be changed. This is about a $200 process to do. It takes 11gal of Super UDT. Which is about $200 worth. Does it need changing every 400 hrs and is there something I can use that is cheaper and just as good?

He changes the oil at around 100 hrs but I don't think he has done much else. So what else should I be concerned about. I figured I would change the coolant and maybe the front axle fluid.

Perry

You should change your vendor. There is no world shortage of second-hand tractors in a rainbow of colours. Look for something with a better service history.
Don't be frightened away from something that has broken, as long as there is documentation that it was repaired correctly. That one you're looking at is just waiting to break still.
:2cents:

 

[rScotty]

Two years ago I bought an obviously hard-used GlideShift with just over 6000 hours showing on it. No telling what the real number was, but certainly had that many hours. It had no service history, but nothing would surprise me about it. This was the utility tractor for a large cattle and grain ranch.

I drove it around for half an hour. The fluid on the dipstick looked good and it ran well and shifted like it should. Solid with no slippage and no jerks.....so I went for it. Changed the filter and fluid and scrutinized both. They looked good. Been using it for a couple of years now and it works fine. A brand new transmission couldn't work any better. I'd say try it and if you like how it works that's good enoough to go for it.
Neither Life nor Machinery come with absolute performance guarantees. Go with what works good today.
rScotty

 

[perryg114]

Well I did a more detailed inspection of the tractor today and it has been neglected to some extent. There is a transmission fluid leak coming out of the clutch housing drain plug. The bolt with the hole in the middle that is supposed to have a split pin in it. It is dripping enough that in a few minutes that there is a small puddle of fluid on the ground. I am thinking that this means there is a leak around the transmission input shaft seal that is filling the clutch housing with transmission fluid. I think you have to split the tractor to fix that. There is a smaller leak at the back where it looks like the gasket needs replacing on a square cover just in front of the axle housing. There is drain plug in the middle of that cover. I am not so worried about this one.

Everything worked as far as the transmission and hydraulics. The loader works fine and it would lift the front end off the ground. I am not sure that this tractor is such a good deal if it will require the tractor be split.



Perry

 

[MHarryE]

Well I did a more detailed inspection of the tractor today and it has been neglected to some extent. There is a transmission fluid leak coming out of the clutch housing drain plug. The bolt with the hole in the middle that is supposed to have a split pin in it. It is dripping enough that in a few minutes that there is a small puddle of fluid on the ground. I am thinking that this means there is a leak around the transmission input shaft seal that is filling the clutch housing with transmission fluid. I think you have to split the tractor to fix that. There is a smaller leak at the back where it looks like the gasket needs replacing on a square cover just in front of the axle housing. There is drain plug in the middle of that cover. I am not so worried about this one.

Everything worked as far as the transmission and hydraulics. The loader works fine and it would lift the front end off the ground. I am not sure that this tractor is such a good deal if it will require the tractor be split.

View attachment 524769

Perry

Perry - when my L5740 did this it was the seal on the front wheel drive shaft exiting the transmission. I believe it is the same setup hydro or glide-shift. Requires splitting. Some have done this by themselves but I chose to take mine to the dealer where it waited in line for others needing the same seal replacement. My oil was replaced much more frequently than specified so that wasn't reason. Its the nature of the beast - some are going to leak and some last.

 

[perryg114]

How much did the repair cost you to have done? The bottom line is that it needs to be fixed. I would think that having oil in a dry disk clutch would not be good. What else will fail once this is fixed?

The good thing is that the fluid is clear and does not appear to be contaminated. I may end up using the B7800 with the 6ft belly mower to mow for the short run. It is a bit small for 44 acres but it will sure mow some grass. It has a 35HP 4 cylinder engine compared to the more noisy 3 cylinder 34HP in the L3430.

Perry

 

[perryg114]

Well I decided to not buy the tractor. It was probably a good deal but I did not want someone else's problems. If the seal was the only thing wrong with it and it had been properly maintained that would be different. I guess I am not redneck farmer who keeps stuff running with bailing wire and duct tape. I also did not like the computerized GST transmission that was 15 yrs old and has had no maintenance. Electronic stuff does not last forever and when it goes it is not cheap. The guy had enough money that taking a $21,000 tractor and running it into the ground did not bother him. He is through with it, so it was a good deal for him. 15yrs of abuse and no maintenance. I look forward to the time when I have enough time to put into projects like this.

Perry