I HAVE A FORD F150 WHEN I PRESS THE BRAKE PEDAL IT FORCES MY FOOT UP AND DOWN QUICKLY. THE FASTER THE TRUCK IS MOVING THE FASTER THE PEDAL GOES UP AND DOWN. IT IS DANGEROUS TO DRIVE ANYWHERE. IS IT THE MASTER CYCLINDER BRAKE VACUUM POD OR THE REAR ANTI-LOCK MOTOR CAUSING THIS?


(This post was edited by snakemanpro1 on Jan 20, 2008, 12:00 PM)

This even has anti-lock? Generally if anti-lock goes into that mode it will vibrate funny and you will feel your pedal vibrating and sink a bit towards floor. If there's a problem with the rotor or a bad problem with a wheel bearing it could jump back at you.

If you jack up each wheel feel for freeplay with the bearings and or front end parts. Remove wheel and spin the rotor by hand and you'll probably find something way out-of-true about it.

YES THIS IS DANGEROUS TO DRIVE THIS WAY BY YOUR DESCRIPTION,

T
Tom Greenleaf - MetroWest Boston - USA
http://www.acsource.com/

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