So, I pulled out the ole Ruckus last night and put the good ole APM on it again. I have everything plugged up and I go to test it. Did the radio calibration and went to see if everything was responding right. To my surprise, the steering works, but the motor acts like it is trying to turn, but won't and ends up browning out the APM. I checked all my modes and they are all "Manual". Naturally, I begin to trouble shoot. Steps as follows:

Setup:

Ruckus RC Truck

Dynamite Tazer 15T ESC

Fireball Modified 15d  Motor

Dynamite 1800 mAh 7.2V Ni-Mh Battery

Turnigy 9X rx/tx

APM 2.5 with 3DR power module

3DR telemetry Module

1) I pull APM out of the setup and set the truck up as RC ONLY (no APM). Everything works! The steering works and the motor runs great.

2) I then start thinking about other options that would cause this. Timing? It runs fine in RC, just not when connected through APM. ESC Calibration? Again, runs fine in RC (and I can't calibrate this ESC). 

3) Is it a PWM issue? I set the APM back up on the truck and instead of running the ESC to the APM, I place a servo in its place. Servo Works Great, just like it's supposed to.

4) Plug the ESC back in, motor fails and browns out APM.

5) Set the truck back up as RC Only and put a volt meter on the motor leads. 7.6v delivered at full forward on the stick.

6) Put the APM back in the setup and run the volt meter to the motor leads. Again, 7.6 volts at full forward and no brown out.

7) Plug the motor back into the leads.... and you guessed it. Fail and Brown out.

8) Pull the motor apart and check it out. Everything is in tact and looks good.

9) plug the ESC up to a separate receiver and power it up with the motor attached (no APM). Motor runs great!

10) Looked through the full parameter list for any possible parameter that could affect this, but everything looks good. I have also tried firmware version 2.46, 2.45, 2.44, 2.43 and 2.40 with the same results.

I'M STUMPED!

with or without the APM, the ESC delivers 7.6 volts, so I dont understand why it only works without APM in the mix. Its a DC motor.

Any ideas?

P.S.  I just checked the output from the ESC power and it is reading 5.8 volts. Could this have anything to do with it? 

P.S.S I just removed the power wire from the ESC and put the jumper on the APM to power both rails, giving it 5 volts on the output rail. I plugged in the ESC and still, the motor is acting up and the APM still browns out.