When you get it back check blade tip speed with a digital tachometer. ( record it ) Put the mower in the grass wide open ( make sure your blades are sharp, balanced and the deck is leveled to spec.) and look for "barber chair" stumps left in the cut. If you experience this at a normal rate of speed in 5 inch height grass with the dial setting at 2.5 suspect the dealer has the PTO clutch engage lever set too loose and in time will burn out your new clutch disc and friction plates up again. To increase tension on the clutch ( proper engagement = correct blade speed ) increase the length of the factory spring setting from 2.68 inches engaged to 2.75 inches for a start. If the Deck is cutting good at this setting leave it along. ( a good level cut with no stumps left in one pass) When you get the initial 50 hours of break in on this transmission use only the factory filters and the Super UDT. Contrary to common sense, these synthetics lubricate better in metal to metal friction and thus keep the noise down you experienced on the old HST. Check the HST fluid ( dip stick under the seat ) before every cutting. Your new HST only hold .9 of one US Gallons of SUDT. A simple DRIP CAN BE DISASTEROUS for this small case sump. This Tractor, its concept and the mechanism are complex to the novoice. Seek help immediately if you experience problems with this tractor that you don't understand or could careless about but seems wrong to your common sense on how it should move and cut. Good Luck to you Red Oaks from Ob1.....