A friend recently purchased an early 04 Silverado 2500HD. He hit a deer last week and needs to replace one of the fog lights. The local dealer is saying that there are two possible fog light assemblies available depending on his VIN. We are wondering what the difference is between the two fogs. My 07 fogs will accept 9005 bulbs but his fogs will not. Is the difference between the old and new fog light housings that they take different bulbs?

My fog lights use 9145 bulbs and I have an 04 GMC

There is a Fog Lamp with a Cap over the Bulb, and one with no Cap over the Bulb. You want the one with no Cap...or the '06-'07 Fogs.

There is a Fog Lamp with a Cap over the Bulb, and one with no Cap over the Bulb. You want the one with no Cap...or the '06-'07 Fogs.

His 04 lens does not have a shroud over the bulb and neither do my 07 lenses. The difference appears to be the diameter of the base of the bulb socket. The 9005 bulbs fit my fog lenses but the the base is too big for them to fit in his lens.

From '03 to '07 Classic the Bulb Size is 9145. A 9005 / 9145 / H10 Bulb will fit in those Spots, no problem.

It's not that the Base of the 9005 it too Big to Fit in his, it's the O-Ring on it. Change it to a 9145 Ring and it'll Fit just fine.

OK I'm stupid! I was trying to put a 9006 bulb in the fog lamp. DUH! I picked up the wrong bulb and thought I had a 9005. Thanks for the help!!!