Glide Shift(GST) vs Hydrostatic(HST)

[Vincent]

Who has experience operating both GST's and HST's in Grand L series Tractors? I would appreciate your comments regarding the relative merits (as well as drawbacks) of these transmissions for tasks such as loader operation, road maintainence, and cultivation.
At this time I'm biased toward the GST as the gear selection can be used to control ground speed while the throttle maintaines engine RPM and implement hydraulic performance. It seems to me that the HST varies both these parameter at the same time. I have experience with manualy geared equipment and know that is not the way to go for ease of operation or safety but do not have actual experience to properly evaluate the relative performance of these two well enginerred transmissions.
Muhammed has continually improved this site and I have enjoyed reading the fine, often spirted theads on this board for the about past year. While this is my first post I am confident that the collective experience of the users will help me make the right decision when the time comes.

 

[MChalkley]

Vincent, would you do me a favor while I work on a reply to your question? Click on the 'Archive' link at the top left of each page, then go to 'Keyword Search' and search for '+hydrostatic +gear' in the Kubota forum. That should point you to the times we've thouroughly thrashed this one on the old forum, but we might as well do it again on the new one...

 

[MChalkley]

Vincent, I traded a '97 L3600GST for a '99 L4310HST so I could get the hydrostatic trans, so that tells you where I stand, if you haven't already found out from the archives.

There are two areas I can think of in which gear transmissions excel over hydrostatics: when precise ground speed control is critical, and when using the tractor extensively for plowing or pulling other hard-to-pull ground-engaging implements.

It's usually not very practical to control ground speed with gearing alone. Far better to set the engine to produce the power and/or hydraulic flow you need and vary the ground speed with the transmission alone. Diesels work best when set to an appropriate rpm and left there. I burn at least a third less fuel on my more powerful L4310 than I did on the L3600, primarily because I'm not messing with the throttle all the time. Diesel tractors bear no resemblance to gasoline cars when it comes to performance characteristics.

Contrary to what you said, the HST does not vary 'both these parameters at the same time', though I'm not sure which two of the three you mentioned you were referring to. The HST pedal only varies the ground speed of the tractor, by changing the effective 'ratio' of the transmission. It's really controlling the speed of the pump and motor in the transmission, but has the effect of varying the ratio in the process.

Aside from the two exceptions I mentioned earlier, I've found hydrostatics to be infinitely easier to use (pretty important), safer (more important than anything else), and more productive (very important to me). Do you want more details/evidence? I don't want to be too skimpy with the info, but I don't want to repeat myself unnecessarily, either. Like they say: You make the call. /w3tcompact/icons/smile.gif

 

[MChalkley]

I can't believe the "brain trust" is going to leave my post to stand without comment. Surely you guys have something else to add... /w3tcompact/icons/smile.gif

 

[gordon]

For me it's a tough call both have good and bad points. All in all if I were to buy a new tractor it would have the glide shift trans, because of what I use my tractor for. For loader work a hydro would be better. I do believe a hydro is the safer of the two but the hydro pedal and brake can be a real pain for me. I do alot of brake steering while pulling and feel more comfortable with the glide shift---Thats my two cents worth

 

[Anonymous Poster]

Since I decided on an L35 over a L with an aftermarket hoe my choice was made for me (GST) but it would have been a tough choice. I have a BX with a hydro and the L35 with the GST. I'm happiest when I can just get on something and use it. 17 years with a Gear tractor made the L35 a dream, no bending to shift, no clutch to use unless you want. Full power but good speed control as the engine is so torquey it goes up easily at any rpm. The hydro is fun on the BX but I haven't got to the point that I can stop and backup and go forward without jerking myself to pieces, and I'll probably never get used to it since I don't have to worry about how I release the throttle on the L35. The HST models have no where near the hydraulic flow that the L35 has, and an aftermarket backhoe even a frame mount didn't fit my bill so the choice was made for me. Fortunately I'm happy with it. I still don't understand how an HST is safer. Maybe if you're planning on having a heart attack while driving. I still wonder why Kubota does not put the HST in the "industrial use" L35 when it's a kissin' cousin to the L3410. That aspect still sends up a red flag (to me). People that are buying these are using them as a loader and wouldn't buy them if they didn't work.

And the brakes are another item. I use the tractor for moving cars, stumps in tight areas, sometimes if you can't brake turn you can't move the object where you want it. I agree with previous discussions on general turning, even in tight areas, with the HST you can slow it down to .0003 miles per hour and creep around an object (of course isn't that less productive, going SLOWLY (hee hee Mark) when you can pivot at max speed? (great for scaring the family) OK Mark, your turn.

 

[Thomas]

Good Morning Vincent.
When I bought my Kubota I wanted a front end loader which I knew I was going to be useing alot,brush hogging,removing rocks,land scaping,snow removeal etc.. and I choose HST.
I'm very please w/ the HST.
Can you compare GST & HST at your local dealer....in a practice pit ?
Take Care.

 

[PaulB]

I am going to answer this post as I did the one on the L2500 and live vs non-live pto...WHERE IS YOUR DEALERS HEAD, UP HIS BUTTOCKS? How can you walk out of a dealership and not know that HST affects only ground speed, if the dealer is doing his job? This is called education not just making a sale. Of course I think you should get HST, precisely because you wnat to be able to run at full rpm with unlimited control of ground speed, but I am more distressed at the fact that your dealer didn't tell you this. Maybe you have only been window shopping so far, and if so I apologise for being critical, but maybe I am spoiled by having a good dealer who really TAUGHT me what to look for in my tractor. And del, as far as safety I believe the main point is that the time required to simply lift your foot off the HST pedal MUST be less than the time required to push in the clutch and release the throttle and shift into neutral in a panic situation.

 

[art]

Mark, this doen't happen to often but let me take advantage of your opening. If you need to maintain a constant ground speed how do you do it with a gear or gst transmission? The only one you can go over hill or dale at a constant speed with is a hydro.

 

[W5FL]

Did I miss something? /w3tcompact/icons/blush.gif My Kubota is a gear (only way it comes). It goes over hill, dale, hood high grass and the ground speed doesn't vary any at all. The Diesel just takes a little more fuel and keeps a constant ground speed. That is the main disadvantage of the hydro and the advantage of the gst and gear transmissions is that they DO maintain constant (and very predictable) ground speed.