I replaced a vacuum booster on a car a couple of months ago and no mention was made of having to replace the master cylinder for the warranty to apply. There were several warnings about side loading the piston in the booster. Obviously you'll want to make sure the seals on the master cylinder are good and not leaking , but I don't know why you would have to replace the master cylinder if it is in fine operating condition. For the auto e-brake release, there is a little white moon shaped vacuum actuator on the lower part of the steering column. These are common source of vacuum leaks. http://www.crownvic.net/ubbthreads/ubbthreads.php?ubb=showflat&Number=1452538
Yeah. But, to be fair, if your booster's going bad, it's usually because the MC is leaking into the booster body. Look at the bottom of it, under the MC. If it's all rusted, chances are the MC is bad.
Bottom line is the most they can say is if the m/c is leaking and you don't replace it then it will void the booster warranty. Obviously you would want to replace or rebuild the m/c if it is leaking. They cannot force you to replace a master cylinder that is otherwise in fine working condition. Of the last two boosters I replaced one just plain had a bad diaphragm. The other was full of water (f&*$ing BMW).
Yeah I see what your saying. If I brought it back and it had brake fluid in it/ on it that might void the warranty . Oreilly's is pretty good about returns. I have friend with a 02? Tahoe that has coolant hoses which are "made together" with a plastic junction in the middle. Why you would make something for fluid that is 200 degrees out of plastic is beyond me but they done it. We had the part but had to go back to o'smileys (2 and three trips are par for the course for me) to get another little special coupler. I stopped at another parts store( the boy calls other stores, "red Oreilly's") just because it was closer. They were out of stock so we drove to o'reillys, got the part and returned to the car. It was just a matter of removing the old hoses from three places I think it went from heater core, to water, pump, and then radiator, all one "part". I got these hose clamp pliers that work pretty well so I was planning on maybe 20 minutes of work so I had the kids with me 2 and 3 years old and my friend can watch them while I did the thing. All is going smoothly, got the old hoses off and went to replace them. Where's the new hoses? Can't find them anywhere. Then I ask my boy. He's three, where they are. "I just threw it out the window, it was an accident " so we back tracked, found them at "the red Oreilly's" in the parking lot. The plastic junction was shattered. Had to drive across town, in rush hour traffic to another Oreilly's who had it in stock. They happily excepted it. Asked what happens and my friend said HE broke it putting it on. He said the lady laughed and told him he should find someone else to do it, as it was in about a million pieces
