When I tried to mow my lawn the other day I pulled out of the garage engaged the mowing deck and got about 30ft. When the tractor just stopped and then it wouldn't go either forward or reverse, I ended up pushing it back into the garage. Is there a belt or something I should be looking for, or could it possibly be low on transmission oil.

There is a belt for the drive that definitely could be the culprit. If you look under the mower in the engine area you should see the main pulley. The bottom belt is for the blades and the top belt is for the drive. Follow the top belt and see if it is broken or off another pulley somewhere.

It could be the transaxle, a idler pulley, the pulley on the transaxle, a missing keyway in one of the wheels etc. Try the belts and we can go from there.

Hi,
I had not answered, but generally there are two idlers, on flat and one V idler that clutch the machine. There a few similar arrangements in them, but they all work about the same. In lieu of the model number little else can be said, except:
OPE by Crigby (http://opebycrigby.tripod.com/)
And look at the "EHP" drive pictures. AYP who is the vendor for most Craftsman mowers has been "folded" into Husqvarna which is a wholly owned subsidiary of Electrolux and is now being separated from the parent, probably for tax reasons. Poulan, Poulan Pro, WeedEater, McCulloch, Partner, Target, etc. are being added to Husqvarna as well. The same servers that allow you to download Husqvarna manuals now supply many many of the other brands as well, though with some "growing pains."
Peace,
Clarke