Product review (4 stars): I recommend replacing this part every 5 years.
I did not know how bad the old shock were. There was no damping left in the old shocks and the upper and lower section literally just fell apart when removed. To test your shock remove the lower mounting pin and if the lower part just seperates from the upper section then the shock has failed. See Youtube video on how to remove shock for mounting pin removal.  I don't see these things lasting more than 5 years on a washer. Now I know why so many washer die from spider or bearing damage. I recommend replacing this part every 5 years or check it annually once it's becomes that old to prolong the life of your tub bearings and the tubs spider support.