Datz510 discovered some time ago a replacement bearing that is in exact fit and it only costs about $6-$7
First you will need to get the bearing at the nearest Checker / Schucks / Kragen or order it online at http://www.cskauto.com/ . Other Parts stores may carry it as well. The bearing is made by Chicago Rawhide and the part # is 62032RSJ
Tools needed:
Ratchet
14mm Socket
12mm Socket
Snap Ring Pliers
1" socket (for tapping out old bearing)
30mm or 1 1/8 Socket(for tapping in bearing)
Hammer
Grease (optional)
To begin, you will need to loosen the bolt on the front of the idler pulley, this will require a 14mm Socket(or wrench).
Second, loosen the tensioner bolt using a 12mm socket.
After you have loosened the tensioner bolt, carefully pull the idler pulley toward you, be carefull as there is a cover and a washer on the front and another washer on the back that may fall off.
On the back of the pulley, there is a snap ring that will need to be removed using snap ring pliers.
Once the snap rind is removed, flip the pulley over to the front side and carefully tap out the old bearing using a 1" or equivelent sized socket.
This is the new bearing next to the old one.
Carefully tap the new bearing in using a 1 1/8th or 30mm socket. Make sure that the socket is on the outer steel rim of the bearing as not to damage the bearing.
Now you can re-assemble the pulley with the washers and covers and reinstall on the truck. I chose to pack mine with grease (on both sides)before hand to try and keep some of the water out but this is optional.
After you reinstall the pulley, be sure to retighten the tensioner bolt. The job should take about 20 minutes and is well worth it.
Good luck!