brake lights

It's behind (towards to the back) of the brake pedal. In a released state the pedal push the switch into it's housing. It's easy to replace. 1. Disconnect switch harness. 2. Press and hold brake pedal in applied position. 3. Rotate switch counterclockwise about 30 ° to align switch lock tab with notch in bracket. 4. Pull switch rearward out of mounting bracket and release brake pedal. INSTALLATION 1. Press and hold brake pedal down. 2. Align tab on new switch with notch in switch bracket. Then insert switch in bracket and turn it clockwise about 30 ° to lock it in place. 3. Connect harness wires to switch. 4. Release brake pedal. 5. Move the release lever on the switch to engage the switch plunger. The switch is now adjusted and can not be adjusted again. Zee

if the brake lights won't come on how can you say the bulbs are good? Does this truck have the transmission interlock where you have to have your foot on the brake to shift out of park? If it does and you can still get out of park it isn't your brake light switch.