Cruise control dead

Your cruise control should use an electronic style cruise control if it is a factory unit. It will be mounted on the driver's side firewall with a mechanical cable leading to the throttle. You need to get your hands on a schemetic of the cruise control. With this you can do an electrical check of the system. The most likely cause is either the cruise lever or a defective brake switch. I've seen many brake switches on those trucks fail, but it only affects the cruise and not the brake lights. The brake switch applies a ground to the cruise until the pedal is pressed. There should be atleast two wires that have 12 volts + on them with the ignition on and two wires that have ground (one is the brake wire) There are also two wires that switch to 12 volts with the set and resume buttons pressed.sparky