Troubleshoot, forward and reverse not working.

[ShopperPEI]

Hello all. I have a White lawn tractor, assuming it's an MTD. I fell off a ramp and rolled. Everything was working fine up until then. Now it starts fine and the blades engage but no movement in forward or reverse. Any suggested steps in troubleshooting? Edit to add that the wheels lock when the transmission is engaged, when trying to push it. Rolls fine in neutral.

 

[bertsmobile1]

Remove the deck and check the drive belt .