MM problems with Hacker

[Unsullied_Spy]

I was going to have my MM sent in for new capacitors, but I got a new Hacker and wanted to test it out before sending the ESC back (since it will be a while before I get my ESC back) and it works perfectly with my Mamba motor but when I hook up my Hacker it just cogs and stutters. I can work it up to half throttle or so holding it off the ground then jump the throttle up to full and it works but from a stop it just cogs. I put it on the ground (this is in an Electric Traxxas Rustler, I should mention) and went to go and it just stutters around. I'm far from overgeared (18/90 right now, I was going to run it with my Badlands in some fairly tall stuff) and everything is hooked up right and I've reprogrammed it both through the computer and the remote and it still won't go. I loosened the motor up and moved it away from the spur and it seemed to work OK, but I'm clueless as to why it won't work when there is any load on it.