Ford Super Duty 4x4 Knob Light Bulbs

2004 F250 4x4 XLT Sport

Shortly after I bought my F250, I noticed that my 4x4 knob did not have any back lighting. I pulled the switch assembly out of the dash and I found the bulb in question to indeed be blown. I called Ford and they told me that this was not a "serviceable" part and that I had to buy the entire switch assembly ($45 in Dec 2007) to replace it. This encouraged me to research further and I found out a few things.

First, these type of 1/4 twist bulbs are called "neo-wedge" bulbs and the company that made these particular bulbs for Ford is "JKL Components Corporation". The typical neo-wedge replacement bulbs I've found have a few problems. First, they are about 1/2 as tall as the 4x4 bulb is and second, the contacts are located in the wrong spot. The replacement bulbs have contacts located in the area shown by the blue arrow in the picture below. The Ford bulbs have contacts shown in the area by the red arrow. I haven't confirmed this but these bulbs might also work for the headlight knob illumination.

I ended up buying quite a few bulbs from ebay that are *almost* exact replacements. The only problem is the contact location problem I mentioned above. So, I simply removed the dead bulb from my original housing, removed a good bulb from one of the new housings, installed the good bulb into the original housing, soldered the connections, and it works like a charm.

So, if anyone happens to have this problem and feels comfortable doing what I did (remove dead bulb/install good bulb) then I can help. I'm going to try to modify these bulbs so that they are direct plug in replacements, but I don't have the time to work on it right now. I will sell these replacement bulbs for $2/each + shipping.

Below are a few pics with some explanation

4x4 Switch Assembly. I was able to pop it out without pulling the dash apart.

Note the 1/4 twist bulb location in this picture.

Original Bulb. I just removed the green rubber cap and re-used it on the new bulb

New bulb. Recall that the red arrow shows original Ford bulb contact locations, blue arrow shows new bulb contact locations.

Here's the bottom side of the original bulb housing, after I installed a new bulb in place of the blown one. I just bent the bulb wires around so they would touch the contacts, and soldered them. Then reinstalled it into the 4x4 switch assembly and it works great.