Small Engines (Lawn Mowers, etc.): AMF(?) Snowblower, wheel option, drive axle

Question
Believe this is an AMF ... model #53621300HD3.  Does not move, Auger and thrower blades spin properly.  Appears all shift mechanisms are working properly as drive axle turns but wheels do not. Lifted wheels off ground, wheels spin freely but not together.  Also, when off ground and engaged, wheels turn, but not when on ground. Each wheel has about 1/4 inch movement in & out on shaft.  Occasionally, while playing around with left wheel (looking from rear) I feel it "engage" and axle and other wheel turn, which I believe is correct action.  Removal of wheel reveals a "differential" type I'm not familiar with ... has a rocker type ratchet looking device that appears is supposed to engage gears on the inside of the hub.  I suspect this geared hub may be excessively worn. Is there possibly an easy fix or does something need replacing? thanks

Answer
Many of the snowblowers have a "free wheel" option so you move the snowblower around eaiser.  Do your wheels, or most likely the axles, have more than one hole for attaching the rim?  Some units had a device mounted directly to the rim...looked like a big knob you could push in to lock or pull out for "free wheel".

Is there a rubber drive disc mounted in the main fram assembly, under the engine, that is used to power the drive system?
Let me know.
Eric