traxxas udr grinding noise

[ZPETEY]

I traded for a udr last week and it has a grinding noise i can't seem to figure out where its come from. Can anyone point me in the right direction? I checked the pinion on the motor and the spur they was fine and the mesh pin is in the f slot. post a video so you can hear.

https://jmp.sh/mr6Qj6gg

 

[Suburban_Hooligan]

diff mesh is my guess. could need shims, could be damaged. id start with the front one.
my Savage XS did something similar. had to shim the pinion closer to the diff gear.

 

[RustyUs]

Used RCs... I think it's always a great idea to give the whole thing a once over. I don't care how well maintained a person says it is... people forget stuff/jerry riggin'. Start at the wheel hexes/pins and work your way into the diffs.