I just bought a 1992 28' Prowler travel trailer last night. While driving it home, the brakes started locking up when I would tap the truck brakes. My 2001 Chevy Silverado does not have a brake controller. What could be causing the brakes to lock up? Also, the trailer plug looks a little damaged. I am wondering if it could be the problem. Please help. Thanks

What brakes were "locking up" Truck's or Trailer's ?

If you mean trailer brakes...I suspect the trailer brakes are shorted out to the brake light circuit. When you "tap" the brakes, the trailer brakes are getting full voltage. Enough to lock up the trailer brakes.