Truck suspensions are improving all the time, and the role of the shock absorber on your semi truck is more critical now than it used to be. As air suspensions and taper leaf suspensions become more common, keeping up with suspension maintenance has become more critical, and changing the shocks should be part of the maintenance schedule.
Most shock manufacturers recommend that you replace the shocks on your semi every one hundred thousand miles, even if they do not have damage on them, as a preventative measure, but you should also have a mechanic check them every time they change the oil in your truck.
