How does GST work

[BeezFun]

I'm thinking of buying a larger Kubota, the ones I've looked at have GST, don't know how GST works. Do you move shift lever while in motion, do you need to use clutch or slow down? Do you still have a hydro pedal, or do you move the throttle to change speed? Is it still a hydrostatic transmission underneath the different style shifter, or is it a geared transmission?
tnx

 

[avc8130]

I owned an L39 for 2 years that had the GST.

In those 2 years I RARELY used the clutch. The GST has a separate clutch that is immersed in hydraulic fluid and controlled by the machine. To change directions you simply move the lever back and forth. To shift up and down you simply slide the range selector. I only used the clutch when precision work was needed. There is a foot throttle that can be used, or you can set the hand throttle and use the gears to adjust speed. I generally used the foot throttle, unless I was running my brush hog and then I would set the RPM for PTO output and then use the gears/direction selector at full pto rpm. It is a geared trans.

By the time I was proficient, I was very fast with it. It takes some practice, but it can be a very efficient transmission for any type of use. I really enjoyed it while I owned it.

If you have any other questions, let me know.

ac

 

[rbargeron]

...... Is it still a hydrostatic transmission underneath the different style shifter, or is it a geared transmission?.....

It has a hydraulic main clutch, but the trans has separate gears for each speed. It does not have continuously variable hydraulic drive like HST. When you select a speed by moving the lever, it activates a system that automatically clutches and shifts gears. Other TBN posters have pointed out that GST shifting is convenient and positive, but not instant. The clutch disengages for a second during the shift so speed changes on sloped ground take a little getting used to.

 

[avc8130]

It has a hydraulic main clutch, but the trans has separate gears for each speed. It does not have continuously variable hydraulic drive like HST. When you select a speed by moving the lever, it activates a system that automatically clutches and shifts gears. Other TBN posters have pointed out that GST shifting is convenient and positive, but not instant. The clutch disengages for a second during the shift so speed changes on sloped ground take a little getting used to.

Gear changes should NEVER be made on sloped ground while moving. Choose the right gear before you embark up or down.

ac

 

[BeezFun]

So if I'm using the FEL and want to go back and forth a lot, that means I'm moving the lever back and forth to change directions. I normally am using one hand to operate the loader and the other to steer. Unless I can grow a third hand it sounds like using the FEL will be a bit slower if I understand correctly.

 

[David_Kb7uns]

The GST is a computer controlled synchronized gear transmission. The ECU modulates the solenoids that regulate the clutch packs and also the solenoid valves for the hydraulics for moving the shifter forks. It takes into account the engine speed, traveling speed and oil temp sensor when modulating the clutch packs.

The shuttle shifter in on the column and their are 12 forward and 8 reverse speeds and they are grouped fairly good for loader work so no shifting of the gear selector is usually required.

When using the upper gears for transport, I do shift on the fly and use the momentum of the moving machine to make it easier on the clutches.

The GST gives you the function of a gear transmission with the ease of something close to an automatic for shifting.

David Kb7uns

 

[avc8130]

So if I'm using the FEL and want to go back and forth a lot, that means I'm moving the lever back and forth to change directions. I normally am using one hand to operate the loader and the other to steer. Unless I can grow a third hand it sounds like using the FEL will be a bit slower if I understand correctly.

It sounds like that, but really it isn't once you get the hang of it. The direction lever is very convenient and the action is very natural. I never felt it slowed me down running the loader to move snow or load salt/mulch.

I have an HST + now, and unless I am working in an intricate area I don't really see much advantage to the HST.

ac

 

[avc8130]

The shuttle shifter in on the column and their are 12 forward and 8 reverse speeds and they are grouped fairly good for loader work so no shifting of the gear selector is usually required.
David Kb7uns

This is a great point. Forward and reverse gears are matched in sets. It works great for loader work. It takes a bit of a "dance" with the hands, but you can be rapid fast:

1. Drive towards pile in a higher moving gear.
2. Slide gear lever just before engaging pile.
3. Drive into pile.
4. Just as you would normally stop, pull direction lever back into Reverse.
5. Drive out of pile.
6. Slide lever forward and increase gear to transport.

I got REALLY good at it after just a bit of running it. You can be SUPER fast.

ac

 

[BeezFun]

1. Drive towards pile in a higher moving gear.
2. Slide gear lever just before engaging pile.
3. Drive into pile.
4. Just as you would normally stop, pull direction lever back into Reverse.
5. Drive out of pile.
6. Slide lever forward and increase gear to transport.

thanks, that explains it very well.

 

[avc8130]

thanks, that explains it very well.

What are you planning on doing with the machine mostly?

What machines are you looking at?

ac