It is important that you are able to tell whenever your shocks and your struts begin to look worn out. It is something that can be very dangerous if you do not pay attention and end up letting the shocks and the struts go out on your car. This is why you should know when it is time so that you do not put yourself or others in danger.
Visual Inspection
The best thing that you can do in terms of knowing when to replace your struts and shocks is to keep an eye on them. This is something that you can do whenever you are already changing something else out, like your spark plugs. Look to see if they are leaking or damaged in anyway. Even something as simple as them looking worn out is something that you should keep an eye on. The hole does not have to be big for leaks to be easy to see. You will simply need to keep an eye out for any wetness or oil that is on the outside of your shocks or struts. Just touch along the sides of them to see if there is any moisture or slick spots.
Checking for Damage
In order to look out for damage, then you should keep an eye out for dents along the housing, or any mounts that are broken. It is typical for the shocks that came along with your car to be in good enough shape, but may simply not be able to keep up with the demands of your car or truck. If this is the case, then it will be time for you to not only replace but to upgrade the suspension system in your vehicle. You will need to do this with some shocks or struts that are more heavy duty than what you originally had.
Performance Considerations
If you do not see any actual damage on your struts or shocks, then there are other things that you can look out for to know when it is time for you to replace them. Make sure that you keep an eye out for these things as it can be very gradual to the point where you do not even notice it. If the ride seems to be bumpier than it normally is, then this can be a sign. The sound of the vehicle can be a dead giveaway.
If there is a thumping or a rattling sound, then this is something that could mean that the cushion has begun to wear out and that it needs to be replaced. If you happen to be driving on terrain that is especially bumpy, then pay attention to how your vehicle handles it. If it is bouncing more than normal then this could be a sign of wear and tear. If the front of your vehicle tends to dip whenever the brakes are hit, then this is also a hint, also look for excessive swaying when taking a tight corner.