So reverse is smooth. Forward is smooth until it encounters load. Light snow is fine but any significant load and it the forward will start to jerk repeatedly like a bucking bronco. Here in NE Ohio, I don't see that much snow but typically use it anywhere from 5-20 times a season. The snowthrower is 10 years old now 9526dle.

Does this sound like a friction disk issue? The friction disk has some rubber but don't know how much a new one has. I did adjust the throttle cable to account for friction disk wear.