ABS Light
 

This past weekend I took my truck on a 1,600 mile round trip to Ohio to pick up a new boat. While driving the ABS light came on but after shutting the truck off while refueling the light would go off. After driving for awhile it would come back again. I didn't notice anything different about braking unitl I was towing the boat on the return trip. When I would apply the break you could feel the ABS kicking in on dry pavement! I just replaced the front pads a couple weeks ago. Any thoughts on what might be causing the light to come on?