Fun Facts inside Kubota's Grand L-Series Transmission

Neil from Messick's here with another tractor split open to talk to you about. We've got a failure inside of this one here to show you today, another common failure point inside of this that you probably should be aware of. Also, some mechanical hydraulic wizardry in the back of this machine in the glide shift transmission can show you all about how it works today. Spend some time with me this morning in the shop. I got a bunch of interesting stuff for you.
The machine that we're working on today is a Kubota L3940. This is about a 15 to 18-ish-year-old tractor. This particular machine has 4,300 hours on it now. It's owned by a golf course and so it's predominantly used for mowing. The reason that this machine got in here today was because this power shaft right here that takes the main power off of the engine, this is going to slide up into the engine against the flywheel. This is starting to lose some splines right here and slip a little bit creating a racket and grinding when they're trying to use the machine. Not a hard repair for us here, to simply pop this thing apart drop a new shaft in, bolt the thing back together, and off we go. But, there's some other interesting bits in here as well. We've got a couple of aspects of this assembly that we're going to talk about here today.
The most common failure point here, the most relevant information to all of you would be a common failure point that we see with this bottom shaft here. Now this is your part of your four-wheel drive. It runs the power from the front of the tractor to the back. In the middle of the tractor right here you have a section of the machine that's supposed to be dry. Normally you're going to have a clutch plate sitting in here that's going to engage a PTO, take the power on and off of the transmission. Now where we see here, is that you've got some seals and gaskets and stuff down here in the bottom that are keeping the oil on the one side of this housing and not allowing it over to the other. Over time, you can have some seals in here work their way forward either just by the motion of this shaft or this thing walking forward a little bit that allows some oil to seep through.
Now Kubota has a solution to this. In the bottom of this assembly right here there's a little pin valve. In the bottom, you'll see that pin come out at the bottom of your tractor. You can push that pin valve up in order to drain the oil out of this dry section here in the middle of the transmission, but if you don't do that and this bottom shaft here for your four-wheel drive is is spinning, it's going to start slinging some of that oil up onto the clutch plates and it will start to allow those clutch plates to slip. That's going to be the side effect of where we see the failure happen here. Now this is another part of the machine that Kubota has improved over time. You see this sleeve right here. This slides over top of this shaft sits against an O-ring back here so it doesn't rattle around and pins all of these pieces together so that they don't move.
While today we're working on this upper shaft up here, we're going to be installing some of these additional components down here on the bottom to prevent future problems from happening. You're going to find this included now on all of the newer tractors. This machine is pushing 20 years old now and just another cool place to be able to see how they continue to improve and evolve these products over time. When you have this thing split open and you look around the insides of it you can't not be impressed. The guys that are here with me are making sure that I don't say dumb things. Look at the inside of this and call it simple but at the same time like mechanically gorgeous, right? This is a transmission that's not seen a whole lot anymore. This is Kubota's glide shift transmission.
It was popular decades ago. It's a cool gear-driven transmission that you can shift the gears on without having to clutch the tractor. The machine will do all the clutching and shifting of the gears automatically and it gives you that really good like power to the ground and efficient transmission that you get from a gear drive machine but with a lot of ease of use making it very easy to drive. Really the reason this thing didn't pick up super well and sell in high volume was because it is essentially about the same price as what a hydrostatic transmission is. That's overall going to be easier to drive. That really ended up becoming the predominant seller so this thing has fallen out of favor now but what it does is awesome. The piece that's right here in front of me has a couple of solenoids on the front and those solenoids are going to shift these valves here in the inside that move these pistons back and forth and shift the components inside of the transmission.
That plate that I was holding here is going to close over top of this side of the transmission here. Then these pieces right here can be actuated back and forth in order to do the shifting. You'll also see these small clutch packs back in here again. This whole transmission is a big electromechanical design that makes this thing really easy to run. It's fantastically reliable and if you have to work on it, you're scared of the electronic components, they're all on the outside of that plate. You can get to them without having to split in and dig into this part of the transmission. It's pretty cool.
Wish we saw it a little bit more still today because there's a lot of innovation here that unfortunately isn't on the market in the same way as it used to be years ago. If you're shop it for a piece of equipment and we can help or if you got parts or service needs for a machine you've already got, say you're digging in here, we're around to help. We're available at 800-222-3373 or look us up at messick.com.