It's not in my garage, but here is what I use for the 50 inch in the living room. Search for an articulating mount. I've got an OmniMount (what you see in the pic, UCL-X) and a Sanus (unused).
Depending upon how big your TV is be careful about how much weight you hang on your wall with one of these articulating mounts. This will extend 30 +/- inches from the wall, pan left/right, rotate left/right, and tilt up/down. It is quite a piece. I think the mount itself was about 40# The TV is around 90# so with it fully extended that is alot of weight acting upon the framing. I did a very significant amount of additional blocking and bracing when installing this mount. One draw back is that the ability to extend from the wall means that at its most collapsed position it stands off from the wall a few inches. Mine is mounted in a recess in the wall so it's not too bad. Let me know if you have anymore questions.