Pulsating Brake pedal

2001 Mitsubishi Eclipse (No ABS). 300,000 miles (really). Runs great. I put front pads and rotors (new) and the pulsating stops for a month at the most then returns. Not constant but under stress (high speed) it really vibrates the pedal and front of the car. Has been happening for the last 4 years with at least 7 brake and rotor changes. Any ideas? The pads that come off look like they are wearing evenly.

Have you changed the calipers? Maybe they are sticking and overheating the rotors.
Did you buy good OEM or better rotors, or cheap Chinese ones?

What tardis said. You need to make sure that the calipers are not sticking - at the very least clean and recondition the slides. And don’t buy bargain basement rotors - spend a bit more money on those to get decent quality.

Some other common errors:

  • make sure that the hub and rotor mating rotor surfaces are clean and smooth - no rust or dirt globs or anything like that.
  • find the correct torque specs for your lug nuts and reinstall the tires with a torque wrench.