diffs
 

To make stronger diffs, do I just change the housing to aluminum? Or do I have to change gears too. I have seen a lot of confllicting info about it on the traxxas forum. So I decided to talk to you guys. I have heard about shimming although, I am not really sure how to do that. School is starting soon, so I want to keep costs down. Right now I have the HV but eventually want to upgrade to the 9l.

What you need to bullet proof your diffs are diffcups and diffhousings from aluminum. combine that with the proper shimming, and you will have got the stuff needed to build very strong diffs.