Hello! I just purchased a 2004 Silverado 2500. After driving it a little bit I've noticed that my cruise control is acting up to the point where it is pretty much unusable. When I have the cruise engaged, it is extremely sensitive and even the slightest hill causes the truck to downshift and hammer the throttle causing the truck to lunge forward. Sometimes this causes the cruise to kick out. Any ideas of what the problem may be? Thanks!