I will probably regret getting back into this discussion, but here goes on my take as to how it works and why it doesn't. Most braking systems use a drum or rotor that is grabbed by a shoe or a disk brake pad. In both of these systems, the units are run dry. If Kubota had installed a brake rotor on the axle just inboard of the rear wheel, then it would act as a service brake and stop the tractor. It is my guess that they didn't feel there was a need for this, since the hydro pedal when you let up on it, is supposed to stop the tractor. There are two problem with this scenario. One the hydro pedal doesn't snap back to the neutral position like it did when the tractors were new. This is a manufacturing defect in my opinion in the Kubota BX series that Kubota has steadfast denied and will only correct if you have a selling dealer that is really going to the mat for you. Most dealers don't want to get into the repair, since it involves tearing down the hydro unit and replacing some internal bearings. This is a difficult and expensive job that Kubota in all probability doesn't pay the dealer sufficiently for. If it takes 12 hours, then they might only pay 10 hours and at a reduced rate. I believe that this has been corrected on the second generation of the BX tractor series.
The second reason that the brake doesn't hold the tractor is that it is internal to the hydro and it doesn't have enough friction to overcome the rolling forces that are present when the hydro is in neutral and the machine starts to move. Once this happens, it is difficult for the forces that you apply to the brake pedal to be transfered to the small mechanism that is designed to only hold the tractor once it is stopped. Try to stop your car using the "emergency" brake only when it is going 20 miles per hour. You will find that it is going to slow the vehicle, but not as fast as you might expect. The emergency brake on a car is also designed to hold the vehicle once it is stopped, but not to stop the vehicle once it is rolling. Someone mentioned a while back to carry a anchor. I have more than once put the loader into the ground to keep the tractor from rolling once it was stopped since the brake on the BX wouldn't hold the tractor on the slope with the transmission in neutral and the engine off. I have learned that the brake is only for holding on just about level ground, but not much more. When I know that I am going to be working on a slope, then I take the wheel chock from my ambulance and use it with the BX. More than once, I have felt that if the BX were to stall, I might go off the end of a cliff. For this reason, I don't take the tractor in many places that I had hoped to use it. The BX is a good machine, but don't ever over estimate its capabilities. If you do, you can get yourself into trouble real quick. It is a great flat land machine, but on steep slopes, it can become dangerous.
