There have been a few minor changes made to the 2018 Super Z HD. The front caster bearings have been changed to tapered bearings, and the claim is they are heavier duty bearings. The fuel tanks are of a different design, a look I personally do not care for. The rear bumper has changed to offer a heavy duty hitch (no photo). I personally believe these changes are no more than a slight difference to make buyers believe the 3% increase in price is showing added value. The heavier hitch may add a small amount of value to a number of specialized customers. The change in their deck height adjustment may appeal to a certain group of customers, but their old design has worked extremely well for many years. The claim is their new deck height adjustment is fool-proof, along with being easier to raise and lower. The design does look nice, but to say there is added functionality, this will be decided by those that have experience with both the old, and the new. I was also told the top of the deck is now built with thicker metal, another point of advertising added value to warrant the increase in cost. The Hustler Super Z deck has never lacked for strength in any area. There is also a difference in deck hanger design, you notice there are no more chains, this may be the best change, but only time will tell. I've never seen, or had any problem from their old deck hanging design.