Posted by canguy: "What do you mean by 'safety notch'? The brake should be on or off." That is what I thought as well - The Brake should have an on and an off setting but I seem to be able to move it to 3 positions (Brake Off, Brake On, and the 3rd which is one beyond Brake On). When it is moved into this 3rd position the chain will move when revved. Prior to this problem starting this afternoon I had only noticed the On and Off positions of the brake. As for rim or spur sprocket. I am not sure, I did not take anything apart at this point. I am assuming it is a rim sprocket.

I ordered the parts today and was told by the dealer that the parts will be in this Wednesday. Is changing out the pads a difficult procedure to do? Will I need to jack up the tractor? Also, from tomplum's posting how do I "verify that the 2 pins that the brake actuator push into the pads are working freely"? Will these pins be obvious? Please advise. Thanks, Jim

These are difficult complaints. If the tech cannot confirm the complaint, then he/she really does not know if anything they try to do is going to have a result. Plus, there are other details that like it or not have forced shops into a defensive position. 1. If the shop replaces the master cylinder, there is no gurantee they will be paid. There is also no guarantee that the car will be fixed either! The problem could be in the ABS system, and one or more of the "vent valves" in it could be seeping. It's also quite possible a tiny piece of some type of debris is moving in the fluid right near the compensating port inside the master cylinder, and causing the bypass valve to not seal after a pedal release. The bypass valve in the master cylinder is designed to prevent the system from going into a vacuum as the pedal is released. 2. If the shop replaces the master cylinder, and the car is not fixed the finger pointing really starts. Many techs feel that with a random pedal fades complaint, that cannot be confirmed the way to approach it is the customer must OK the replacement of the master cylinder, and acknowledge in writing that this service is by choice, and not a guarantee of any repair. In the past, techs would do the master cylinder and since there really was almost no chance that it could be anything else get away with it. But today, there is a significant chance that the failure could be in the ABS, or elswhere in the system. So the customer must agree in advance that if the problem persists, the continued repair is NOT FREE. Keep in mind that refers to non warrantied vehicles in for direct customer pay services. Being under warranty it creates an entirely different senario. But the O.E. has the same interests as the average consumer, they don't want to pay for things needlessly any more than anyone reading this does. All that aside, sometimes you have to do something, even if it's wrong! 3. You say they bled the system, and they said it had an air bubble? So basically, the car went into the dealer with a very low pedal, they bled the brakes and now it has a good pedal. That is a plausible senario, and your claim of it being BS, without testing just might be totally unfair. Air bubbles can occur for a couple of reasons. The air could have been trapped in the ABS system, and released to the brake system. The fluid could have gotten very hot under heavy brake useage, and boiled water vapor, and other gasses out of solution creating a bubble that may have been unable to be reabsorbed by the brake fluid. So lacking any proof otherwise, the tech and the shop have to go with what they can confirm. If you were not there, and did not bleed the brakes yourself then you really don't know if they did bleed air out of the system. Once again, you might not be fair here with your claims. In some ways Lexus has two problems, a car they cannot confirm that is broken, and an owner that dosen't trust them or the car. Granted, I would be very concerned with the car under the circumstances you outlined. Given my own resources if I was in your place, I would replace the master cylinder myself out of pocket just for my own piece of mind. If I get reimbursed, great, if not I have the peace of mind knowing I have eliminated a very likely source of the trouble. One other thing to think about. Your master cylinder controls the LF and RR wheels together off of one piston, and the RF and LR wheels off of the second piston. They do this to try and ensure that no matter what, you at least have 50% of the cars total braking capacity. Sure if one of them bypass fluid the pedal drops, but the opposite pair is being applied ever fuller when that happens. Thats part of how as I tech I figure out exactly what is happening when I have a car with the symptom you have described. You have my sympathy with this situation, and the dealer does too. Once again, for your own peace of mind, and trying to ensure that there isn't a hidden problem I would recommend pay them to replace the master cylinder, and do a brake fluid flush. Then take it up with your selling dealer and see if they can help you out in this circumstance. Remember, without getting to confirm the actual cause, even with replacng the master cylinder, and doing a brake fluid flush you could still have a problem lurking. The only thing I can tell you is you will be the first to know....... :(

If the A.B.S. controler was at fault it will usually set a code. Not the case but your master cylinder will cause that problem. If your brake booster is leaking internally your engine vacumm will slowly apply the brakes. Only seen that once. i'd be looking at the master cylinder first.