I've not researched it at all yet, but I think I have broken my transaxel. Maybe I have just worn out the drive belt, but that looks good on first inspection.
I have a Poulan Pro HD21H42 that has a 314-0510 Hydro Gear transaxel. My big issue with this mower has always been the lack of traction when hauling a trailer full of whatever up an incline that is covered in pine needles. (The incline leads to the wooded area at the back of my lot where I decompose everything; lawn clippings, leaves, fallen trees etc.) So, rather than just fix the lawn tractor, whilst I have it apart, I'd rather upgrade it. Is there a limited slip differential that I can use instead of the stock unit?