A treadmill should be serviced & lubricated at least annually (bi-annually for the most active users). Failure to do so can lead to the most costly of repairs for treadmills: replacement of the belt and deck. This repair averages more than $500 on quality treadmills. This compares to the $90 average cost of a tune-up (assuming you live in Marion and surrounding counties). An ounce of prevention is worth a pound of cure !!
A belt and deck become "married" through time and replacement of one or the other is not advised--they should both be replaced as a pair.
The type of lubrication for treadmills can vary greatly and use of the wrong lubricate will destroy the belt / deck combination.
Please consult your owner's manual carefully or, better yet, contact the BGI Fitness Service Department to insure you are using the proper lubricant.
Remember also that poor lubrication increases the heat build-up of all of the electronics in the treadmill. Heat is the number one enemy of electronics.
If you are a do-it-yourself kind of person, that's great. We suggest you schedule a tune-up on your treadmill and be there to observe the materials and techniques used by the technician so you can replicate these procedures on your own. Your technician will also be able to supply you with a quantity of the proper lubrication materials.
In summary, there is a compelling economic rationale for why you should get a tune-up on at least an annual basis.