Glide Shift(GST) vs Hydrostatic(HST)

[W5FL]

Del,

The only choice I had was a gear tractor so my comments should be taken as such. The brakes on my Kubota are absolutely wonderful. They hold the machine in every conditions I have had it in when running. The brakes were absolutely worthless on my previous tractor (A Massey) and the only brakes on the old Farmall were hand brakes over each wheel (and a crank starter).

I couldn't see anyway to make a clutchless shift without a hydraulic motor coupling, which I assume the GST is. That is synchronized gears with a hydraulic coupling to make it clutch optional. From everyone I have heard about they love the L35. I looked very carefully at getting one because it could do so much in such a small package (and I really wanted a backhoe). My land is almost one continous slope with plenty of rocks for a firm base and I have to use the brakes everytime I stop when the engine is running. I have never had the feeling that the brakes were not going to hold.

The only problem that I have noticed is that the tractor is so strong, that it can't tell the brakes are on. You can take off and the only time you would know the brakes were on is when you push in the clutch to shift gears or stop. Then the brakes bring you to a slamming stop, so they really work well.

Anbody invented a "BRAKE" warning light yet?

 

[del.]

I'll accept that the parking brake is strong, maybe I'm just stuck in the past and still believe in Murphy's law, what can go wrong will, and when I have a 6000 +lb tractor on even a small slope I'd like a secondary source. I can always stick the backhoe teeth in the dirt if I'm holding something with the loader I suppose, or maybe I could buy Mark's extra loader cylinders, attach some sharped steel posts and mount them so I can hydraulically stick them in the dirt when I stop! An automatic in a car has a park position why can't a tractor? Why couldn't that have been designed like the air brakes on a truck, so when there is no pressure (engine off or air pressure failure) the mechanism locks up.

The reason I chose the L35 is that everything ELSE about it is above what I could find elsewhere unless I went to a much more cumbersome unit (which I couldn't).

Thanks for your post.

 

[Bird]

del, I agree that I like the double protection feature, i.e., a "Park" position for the transmission as well as the parking brake, and I would assume it's just a matter of cost, but I've also driven diesel trucks and diesel motorhomes with Allison automatic transmissions and the only thing that holds them when parked is the park brake, and in some instances that's on the driveshaft. At least the park brake on the tractor locks both rear wheels, and I've never considered it to be a big deal. I fully expect the brakes on my tractor to outlast me, but if they ever do show signs of wearing and not holding, you can bet fixing them will be a top priority.

Bird

 

[MChalkley]

Wen, the mechanism that allows shifting between gears in the GST transmission is a hydraulic clutchpack. It is engaged by pressure from the hydraulic pump, which is why it isn't engaged when the engine is off. Other than that, and the control mechanism to tell it when to engage and disengage, of course, it's just a clutch. So, the GST has two clutches, the hydraulic one and the manual one. Both have to be engaged for the tractor to be "in gear" in the sense that it won't roll, and unfortunately, as Del found out, the hydraulic one can't engage without pressure, which requires the engine to be running. Bummer. I wonder why the designers couldn't have engaged it with a spring or something and disengaged it with pressure, like the air brakes on a truck do (for obvious reasons).

The L-series tractors have brake warning lights...