True Fitness 400 Series - Manual (Page 11)

Treadbelt Adjustment
8
1. Stand beside the treadmill, place the safety key onto the
control panel and follow operating instructions for running
the treadmill at 5 mph.
2. If the belt is off-center to the right, turn the left roller
adjustment bolt counter clock-wise 1/4 turn. If the belt is
off-center to the left, turn the left roller adjustment bolt 1/4
turn clockwise.
3. Let the machine run for several minutes to check the
alignment. (Belt alignment does not need to be perfect). If
more correction is needed, turn the adjustment bolt 1/4 turn
and check again.
Treadbelt Tension
To assure maximum life of the treadbelt, roller and drive
motor, make sure the treadbelt tension is set correctly. (Your
treadbelt has been properly tensioned at the factory.)
Turn both rear roller adjustment bolts counter-clockwise
until treadbelt just begins slipping when walking on it, then
turn both rear roller adjustment bolts clockwise in equal
quarter turn increments until treadbelt stops slipping.
Note: Be sure to run on treadbelt to ensure that the
treadbelt does not slip while under load.