Will these plug directly into my truck without wiring changes?

Yes. These use factory connectors and mount at the original fog light points. Swap them out for your stock units and you're done—no splice, no adapter harness needed.

Are the lenses prone to fogging or clouding over time?

Clear polycarbonate housings resist yellowing better than older acrylic plastics, but any lens exposed to UV and road salt will eventually age. Periodic cleaning with mild soap keeps them looking sharp longer.

What's the actual brightness difference compared to halogen fog lights?

LED output is noticeably whiter and more focused than halogen. You'll see better contrast in fog and low-light conditions. Exact lumen specs aren't published, but the shift from warm halogen to cool LED is immediate.