So I'm having an interesting issue with my 93 W350. This truck just seems to like headlights. Since I've owned it, typically I replace 2 sets of sealed beams a year, and only have 26-30k miles on it since I bought it.
One of the first things I did was the Jim Lane relay conversion, with the 3 relays for dual beam.when on high, which as discussed before, may be why I burn threw so many lights, cause the bulbs themselves cant take the heat, as well as a majority of my driving is at night, (whoo night shift)
Last Oct, I installed the best Sylvania bulbs I could get, they were the white white ones from Auto Zone, $25/piece. Welp, burned up the driver side Sunday night.
Installed a Wagner I had laying around, and notices it wouldn't light on low beam, but did on high, granted, was extremely dim and yellow, compared to the Sylvania still installed on the pass side. Messed with the wiring, and found when i turned off the lights, the headlights stayed on, and they only went out if I pulled the headlight plug off the drivers headlight.
So I'm thinking a backfeed issue, but why? I did notice the ground terminal on the plug was bulged, and had a burnt look to the plastic. Granted, I don't believe I used the heavy duty plugs, as they were unavailable at the time. I also didn't upgrade the ground wire either, as suggested by others here, ad I just followed Jims instructions.
I'm gonna try and locate some heavy duty plugs and swap em out, but any idea why, even with the relay setup I burned a ground side of the plug? Possibly the Sylvanias were too "hot" electrical and drew too much current for the plugs rating.
I do use die-electric grease on the plugs, possible I used too much and the current was jumping terminals. Lights have always been awesome bright, so its a recent issue with either the plug or the old bulb.
Ideas, comments, words of wisdom?