HRX217TDA Drive problem

[Wayne195]

Trying to help a freind of mine find help with his lawnmower...
His Honda HRX217TDA Versamow (SN#MAGA-1142027) with a 3 speed transmission that runs GREAT but wouldn't move.
When its in gear and you pick the back up a little the wheel go like no ones business in all 3 gears but as soon as it hits the ground-nothing.
He immediately "assumed" that the transmission is ok & there's a problem elsewhere.
So he get a new drive belt-did nothing!
Then he get a new cable-did nothing!
then he spoke to a local Honda mechanic and he says that he has seen the pulley on top of the blade adapter get out of shape and not grip the belt well-so we replace that-which was not cheap!
It didn't help either!
He has the cable adjustment maxed out and there's very little tension-if he pulls on the cable it wants to go-SO he made a quick bracket to get a little more tension on the cable and it STILL didn't work...
Anyone have a thought?? Is the tranny bad??
Any info would be appreciated! Thanks