Mine is burned out and my wife has the car so I can't just pull it and take it to the store, does anybody know what the bulb number would be for a standard Phillips or Sylvania bulb? Both list the front marker but not the rear. I'm guessing it is the same but it is darn cold out to be try to replace it and be wrong.

 

For my wife's 2006 XK8, that particular bulb is listed as a 12V 5W capless long life bulb....

If you find that the bulb is not so much burned out as it is rusted away due to water inside the lamp assembly, Welsh Enterprises sells new rear side marker lamp assemblies complete with bulbs for a very reasonable price. I paid about $15 each back in October 2015. The lamp assemblies are prone to allowing water in as the years pass by....

 

Same as the front - W5W or 501 type bulb.

 

Both the Front Marker Bulb and Rear are the same....The Lens is where the color comes from....It's a little wedge bulb Silver Star (Sylvania) #2825....It is a clear Bulb.....Also the same for the Parking Light.....and probably several more like License Plate........

Billy Clyde in Houston

 

Do you stick the blade of a putty knife underneath the lens to pop it off?

 

Reach underneath the side of the rear bumper and carefully push the lens assembly out with your fingers. There are a couple of metal spring clips that hold it in place. Take a small flashlight under there, have a look at the back of the lens assembly, and you will quickly understand the process....