Chosen Solution

I have a Craftsman 917.376390 push mower, and it seems like the transmission for the self-propelled stuff is locked up. The front wheels, including the axle running through the transmission, turn freely, but the transmission itself seems locked up since the pulley wheel doesn’t turn when the axle does. I tried turning the pulley wheel on top that the drive belt connects to with my hand and it won’t budge. Do I need a new transmission? Is there anything I can do to free it up and save $30 + shipping? Edit: The mower runs and cuts fine, it just isn’t self-propelled anymore.

Does the engine still run and if so will it still cut the grass if you push it. If it’s runs and works. Good guess something under the drive cable to the wheels is stuck or jammed up. May be a bad part or bearing. No one will be able to tell you what it will need till parts are removed and find out what is damaged. If you engine won’t run or turn then your problem my be bigger then a gear or something.