JB, the 3186 has a cast aluminum case without a locking differential. I don't know of any problems with the drivetrain on the 3000 series. The tractor uses a driveshaft for the drivetrain and is not belt driven. The differential could be a problem if abused. The pto shaft for the mower deck is belt driven and that is also okay. The belts on the older cubs had to twist a 90 deg bend to get back to the deck and special belts had to be used or a new standard belt would shred apart. When you look at a 3000 series keep in mind that these tractors were in the $5000 to $7000 range and finding one in good shape for under $2000 is probably a good deal. These tractors can also be equiped with a hydraulicly operated tiller and with a flip of a lever you can run the tines in either direction. Look at the junk the box stores sell for about the same price. Just my
