Big Rock Cogging after harder landings. Won't move..just juts back and forth

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Arrma RC's
  1. BigRock 4x4
Hey everyone... Happy gobble gobble gobble! So my Big Rock has been acting up the last few batteries. I replaced all fans with Yeah Racing Tornados. A battery in and I took a big jump and chassis slapped into the side of a packed dirt mound. Upon pulling the trigger the truck cogged and bounced back and forth a little. Wouldn't move if given a push as well. I turned it off...let it sit...turned it on and it ran, but still cogs. Hit another jump, land.....same thing again. Eventually moves....speed run.....dead battery. Check the battery and there is 9% left.

Any ideas as to what is happening? Is it the motor or is it the ESC? Is the mesh binding?

Any help is appreciated. Thanks everyone!
A video with audio would be helpful. My guess is you lost a phase on the motor. One of your ESC to motor connectors failed. You might need to do some soldering.
I'll try and get some video tomorrow. I appreciate your response. Do you mean the physical connecters from motor to the ESC?
Yes. They have been known to come unsoldered from the factory. Bad, cold solders. If it flexes close to the bullet connector, it's probably failed. Any silver solder spatter in the chassis?
9% left in the lipo is way far too low. How did that happen?Technically that is a fried battery or soon will be.
Yeah look over the 3 Motor Phase wires Carefully for good connection and/or corrosion, Check along wires also. ( these are called 3 phase motors with 3 wires.)
Open the motor, clean and inspect it. Clean and lube BB's . Look over the Armature for damage while in there. Use Electrical Contact spray to clean the motor. The ESC could also be at fault. :unsure:
Process of elimination.
All Wiring and Motor checked first IMHO.
A Video would help us help you better.
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