Ok bought a b2710 and guy said it was having issues with drive. he said it would only work in low etc. so I changed filters and fluid and adjusted clutch some and got it moving in all motions fine well I went to move some dirt and the tractor spun tires at first then caught grip and then it was like clutch was slipping and almost wouldnt move I turned it off and let it sit and pushed the clutch pedal in and out a few times then started it back up and it moved but felt like something was slipping and has a howl noise coming from clutch area but still drove in low med and high gear for and reverse fine. So clutch out or is it possible its the HST?