hey guys i have a 95 f350 with 274,000 miles with a 10 ft service bed. i have a electrical issue going on. i have dash lights, headlights marker lights, backup lights, brake lights all burn bright until i turn on headlights. when i turn on lights all are bright , but tail lights are dim. when i hit the brake, i have no brake lights or tail lights when i turn off light switch, i have brake lights and turn signals. turn signal switch is new, both flashers are new. any ideas guys maybe bad headlight switch. i know how to get the headlight switch out, but have never pulled the stem out of old switch.
I think the headlamp switch is fine. concentrate on the wiring to the rear lamp sockets. Being as bulbs go out when you hit the brakes, i'd start by making sure you have good grounds on both sides and proceed from there.