Draco Meteor is definitely not a good move for Garchomp.
Not only is it troublesome to be able to teach, (maximum friendship) but it is also a Special move, which is Garchomp's worst stat. Outrage (if you have Platinum) would be great, but if you want to teach Garchomp Outrage, you may want to consider giving it a Lum Berry or Persim Berry. Or you could teach it Dragon Rush, which it learns naturally at level 55, but Dragon Rush has low accuracy. Another option for Garchomp is Dragon Claw, which has good accuracy, but is not as powerful as the other moves I mentioned. It is also learned naturally by Garchomp, but at level 33, so you could have actually taught Dragon Claw to Garchomp when it was still a Gabite! Hope I helped! ^-^