I have an '05 F150 FX/4 and I can't seem to keep the water from entering my fog lamps & blowing out the bulbs. I've replace both fixtures with new ones and they still seem to leak. Any good suggestions? This really chaps my a##!

 

Are you using stock 9140/9145 bulbs ?

Are you sure they are installed correctly ?

I could see how the old set could have a cracked seal, but the new ones ( unless damaged in shipping ) should not have this issue.

 

I'm using the 9145 bulbs. I bought a new driver's side assembly from ebay about six months ago. It's sealed around the lens fine because it actually holds water! The bulbs appear to be installed correctly into the assembly.
I may remove both assemblies and re-seal the areas where the lens joins, and see if there's any way to determine if water is getting in around the bulb area.