Good day all. This is my first post here. I hope someone has some knowledge on what may be my problem and thank you in advance. I inherited this beautiful john deere 170. I believe its from 1989!! The machine is strong very very strong. I was out plowing a few days ago and all went well! Last night i went out to plow and in gears 1-2 there was a jerking motion. As i went into 3rd it would just stop moving unless i feathered the clutch in and out. While pushing a load of snow in 3rd it would loose momentum and eventually stop (not spinning the wheels). If i powered into 4th or 5th gear the machine would push no problem like a bat outta hell Any ideas or suggestions on what to check? I appreciate any advice. Thank you!