Well, I was driving my RC10gt around today and all of the sudden, it sounded a little different, the started to pull to the left hard under hard acceleration. So I figured it was dif. related. I took it apart, and the 2 rings were a little groved from the bearings, so I flipped them over with the smooth side to the bearings. Put it back together, and the same thing still....Any ideas? What do I need to do?

When its all together, and I turn one wheel, the other doesnt spin at all...?