I serviced the NordicTrack ViewPoint treadmill in Brunswick, Maine. The belt needed to be lubed and adjusted and the treadmill needed to be cleaned.
I also had an issue with the belt surging, slowing, stopping, then speeding up. I checked everything out before cleaning and lubricating the belt and deck. After lubing the problem appeared to go away.
This was an older, but still nice non-folding NordicTrack treadmill. I liked the large rollers and the 3HP continious duty drive motor.