i have a 2002 f150 4x4 lariat. i have done many many brake jobs in my life time. i have a pulse type problem with this truck that i can't figure out. if i hit the brakes on the hiway say at 70 mph and stay on the brakes while taking a ramp. i get a high speed brake shutter. if i roll slowly to a stop with the brkes on the last 20' it feel like im pumping and releasing the brakes, kind of jerky like. i have replaced and turned the rotors. i stopped using ceramic pads. i blead the brakes. i replced the pad hdw clips etc, when i replaced the pads. i did this to both the front as well as the rear. brakes seem to work well and anti lock seems to be functioning ok. when i first do a brake job every thing is fine, its after a few 3000 miles or so that this happens. i also tow a 7000 pound boat and trailer once a month but the trailer has surge brakes on all four wheels that work fine.
any suggestions?

 

What you discribe is like a change in rotor thickness.
This usually would cause the pedal to pulseate by forcing the caliper piston back in on the high spot areas and pulseating the pedal.
Maybe the rotor goes bad at some part of it's circumference from heat and comes back after it is turned. This is called heat treating it'self and the friction changes in that areas because the metal can get harder and cause uneven over the rest of the surface areas.
You are putting the brakes under considerable hard use by towing.
Good luck.

 

Usually warped rotors or malfunctioning ABS modulator. If the problem is this bad, I wouldn't bother turning them. You can get a good set of slotted and/or drilled rotors for around the same money of stock rotors.

 

i don't think its a warped rotor in that i have two sets of them and after 3000 miles they both do it both are actual ford products. i have no pedal pulse but the vehicle seems to be pulsating and there are times when it will not do it. but 90% of the time it does. it never does it when towing??

 

I know this is an old post but I'm having the same issue. What was the solution?

Thanks,
Tim