Tail Lights Set Left Driver Right Passenger Pair Fits 2004-2007 Cadillac Cts (From:1-4 '04)

You may well have to adjust the headlights after installation. If it's possible, when you take the old assembly out, you should match up the new adjusters with the old ones. Adjust the new light as close to that on the old units as you can. That way, any adjustments you have to make on the car once they are installed will be minimal. Our headlight assemblies have the same or improved adjusters as the stock units, and there are many videos on Youtube on how to adjust lighting. Check your owners manual too, since not all vehicles are adjusted the same way. Finally, when adjusting, make sure your car is level, with a full tank of gas.

HID lights can also be referred to as Xenon bulbs (though not all Xenon bulbs are HID). Some vehicle manufacturers also use Bi-Xenon headlights, headlights which use an HID low beam bulb in combination with a halogen high beam bulb.

For the most part, no. The stock replacement headlight assemblies are a direct equivalent to what is being taken out of the car. You can reuse your old bulbs and sockets, which should fit right in with no modifications needed. Some of the aftermarket units do use different Halogen bulbs than the stock ones. In those cases, we sell the requisite bulb, and really, with the great deal we have on PERDE light bulbs, you can't go wrong with fresh, new bulbs.