I have a couple year old 36" exmark with a 15 Kohler and have been having some abnormal ticking here and there mostly it seems when the mower is on an incline. Today I was mowing along a ditch that wasn't that steep, but the mower started making an ungodly noise. What would cause it to make more noise when on an incline? BTW I am using 10-30 Amsoil and have been since the first of the season. Any idea what the deal is? Or what I can do to fix it?