Reinstalled new front rotors and bearings today after another front rotor warped, causing a pulsing brake pedal. This is twice that's happened.
I had been using a NAPA front hub/rotor with new bearings the first two times. This time I went to the dealer, who had the VIN, hoping to get OE hubs/rotors to avoid the problem. The parts guy gave me the part number correct for the VIN, which was different from all those for the truck online and from RockAuto, and said Ford had obsoleted it. He did find two in the system, one each from different sources, but the price was nearly $200 each. I passed.
The Motorcraft part number is BRRF62; Ford is AL5Z1102A. That was the first time I had seen either part number. I got an aftermarket equivalent referencing BRRF62 and BRRF64 on eBay for about $70 each. Everyone who had the actual Motorcraft part wanted a lot for it too. Evidently the particular combination my truck is—SuperCab with jump seats, 4.0 V-6, auto, tow package—requires this particular hub/rotor, which is allegedly heavier duty than the standard assembly. The ones I had been getting evidently weren't quite up to snuff.
Understand that I don't ride the brakes, do not normally stop hard, and have pulled a light trailer with the truck only once, but the rotor warped anyway. The driver's side bearings showed signs of overheating, but the passenger's side looked all right. I use one of the best synthetic high-temp moly greases available, Red Line, and bearings had been installed to torque specs. The wheels rotate freely with no play.
We'll see how it works this time. Getting tired of messing with these.