Disassemble and clean your dash ground at the left kick panel, next to the park brake pedal assembly; disassemble and clean the cab-to-right rear cylinder head ground; disassemble and clean the battery-to-engine ground; disassemble and clean the battery-to-radiator support ground; disassemble and clean the battery-to-frame ground. In other words, service all the ground connections, but pay particular attention to the cab and dash grounds!
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