I just traded my F-150 in on a 2004, F-350, 4 Door Extended Cab,6.8L V10,4WD, XLT with 75k miles at a FORD dealership. CARFAX shows it being in Southern CA since new and on a commercial lease program. Same dealer has done all required service and I have the information. I noticed a unique wear pattern on the front tires. Not over or under inflation. After driving it a little I picked up a unique feeling I have had on other one ton trucks. When stopping the vehicle feels like it has more braking power with the front wheels than the back wheels. At 47k miles there was a "thrust alignment" done and tires replaced, tire condition and pressure checked and tires balanced. At 63k miles front and rear brakes were replaced, tires were rotated / replaced. At 66k miles a two wheel alignment was done. The dealer service department could not explain the unique front tire wear. The roads have been dry so I have not attempted a hard stop on wet roads. I suspect the front end will slide. This unit spent it's life in SoCal and now I'm in the Pacific Northwest. I'd like to solve this issue before the rain begins to fall later this year. I have read there is a "modulator valve" in the ABS. Could this be the problem? Thanks