The planetary gears are fine, after taking it apart.

I believe the issue maybe with what ever locks the axle in 1 direction.

by hand, i cant get the axle to slip or make noise. the axle spins freely in 1 direction & locks in the opposite.

Thanks for the insight @ handlebar 

it only makes the grinding noise when going up hill it never had issues with prior.

works fine on level ground with throttle.

if you put the front wheel against a wall & throttle it, it makes the noise.

no issues pedaling, pedals normally & no noise when pedaling either.

When on flat ground, the bike rides ok with power, but if i go uphill, there is a grinding noise from the rear wheel & it no longer is propelled.

I pulled the motor & all the gears look fine within the rear hub, nothing eaten up.

Any suggestions?