After a friend and myself found we were having to change the Geetech bearings way to often and having some sets fail after a few prints we thought it was time to fix the problem once an for all.
We had the issue for both X and Y axis.
Here is the Y axis fix http://www.thingiverse.com/thing:1687544.
The problem is the bearing sets Geeetech use are garbage and hard to source unless your happy to wait from china.
Plus the design has had little thought. The roller holder when you tighten pulls the sides in at the front so the roller actually touches the roller holder. Add to that the design doesn't even use the bearing as the bearing centre just rolls on the screw.
So what we did is use a common and high quality roller blade bearing from the local skate shop. I think it's for a roller blade. The ones we used are 12mm wide X 4mm thick with a 6.5mm hole.
Though have uploaded the scad so you can adjust to what you can find locally.
Hope this helps your setup.
Mine broke between the bolt and the end. I do tighten it super tight though. So just uploaded V2 which is thicker. I also used ABS at 100% this time.