So I just got my new Traxxas power cell 8 cell 9.6v 5000mah battery in. I charged it at 2 amps to over 9volts. I put it in my truck and plug it in. The steering is fine but when I push the throttle the truck creeps along. I got the voltmeter and found that it is only delivering 2volts to the motor while the battery is charged over 9. What is wrong here? Btw I have the xl-5 and 550 12t.