How do I remove subdivision loops? I am trying to manipulate a cube into a car; and I was able to make edge loops by pressing  Ctrl+R. However, when I am trying to make a wheel well, I want to make new subdivision loops to do that; yet the old ones are getting in they way.

How do I remove subdivision loops so that I can manipulate my object without old loops effecting the new ones? 

Or basically, the opposite of what Ctrl+R does?
You can select them with AltRMB (or AltShiftRMB to keep the existing selection), and then delete them with Delete > Edge loops, or DeleteG if you want to take advantage of menu hotkeys.



If you have many loops which you want to select, but don't want to click on each one, you can use Multi select loops, either from 3D view > Header > Select > Edge loops, or Space> Multi select loops.