I was wonder how often everyone else hears their master cylinder buzzing with the self check while braking? If I tapp the brake pedal 5-6 times parked in the driveway, the master cylinder buzzes, doing it's self test. It does this every 5-6 times. Is this normal? I'm interested to hear from anyone else with a newer 05 or 06. Mine's one of the original 03's. I'm curious after reading this....http://www.toyota-4runner.org/showth...p?threadid=884

Anyone?

 

Bump, Anyone who can check this for me, please?

 

Mine does this but not loud at all. One time I did hear it loud though, but there was a screw I dropped stuck between the master cylinder and its mounting bracket. Removed that and back to quiet.

 

Yes, a light buzzing sound. It seems to do this quite a bit. I don't know if it's normal seems to be a lot of talk of master cylinders on the earlier 4th gens not working properly based on the above thread.