Everyone needs to realize that while most of the hard work has been done for us to find combinations that work you will still need to do some tuning on your own to get the truck to where you want it. For me the final change was a front swaybar change, went to the yellow bar from blue and now my truck is on rails. Something as simple as a swaybar change can be the difference between an unpredictable truck and one that is consistent lap after lap.
Tuning the handling of any RC is all about balance, if you lack rear traction you need a softer rear end in relation to the front end...Dont limit yourself to going softer in the rear, experiment with going stiffer up front also.