To start, the tiller with the problem is a 5HP Craftsman with rear tines. It just started "squealing" when it is put into either forward or reverse. It still runs and tills. What adds more to the confusion, but is likely diagnostic to those that know what is going on, is what happens in neutral. When you push it in neutral, even with engine off, the machine bogs down after reaching a certain speed. It does not bind up but it does become difficult to push. Does this sound like a transmission problem that can be remedied by a moderate handyman or do we need to take it to shop?