I have noticed that when I am walking/running on my tx400 that when I seem to press down the belt almost feels as if it stops then picks up momentum. Should I tighten the belt and if so where/how should I do that?
It could be a loose walking belt, loose drive belt.
or your belt and deck could need lube.
My video on Treadmill maintenance and How to adjust a rear roller could give you a better and easier clue to your problem.
You can also email me, markepeterson@austin.rr.com
Im a 23 year veteran certified service tech for exercise equipment.
www.mindbites.com/person/214-Mark