My 2009 Nomad now has27000 miles on it, and a few days ago I started hearing a squealing sound as I was letting off the clutch leaver starting off. It seems to be louder while carrying a passenger or starting off while on a hill but it don't seem to be slipping while riding. I'm running Rotella t6 5w40 and it's time to change "5000" miles. Any suggestions about what may be going on. Will the oil have anything to do with it.