How do I know if my vehicle really needs new shock absorbers?
You need new shocks (and/or struts) if your original shocks (or struts) are worn out, damaged or leaking. Leaking is easy enough to see (just look for oil or wetness on the outside of the shock or strut) as is damage (broken mount, badly dented housing, etc.). But wear is often more of a subjective thing to judge. There are also instances where the original equipment shocks may not be worn, damaged or leaking, but may not be adequate for the job they’re being asked to do. In such cases, upgrading the suspension with stronger, stiffer or some type of special shock (or strut) may be recommended to improve handling, for trailer towing, hauling overloads or other special uses.
Shocks and struts do not require to replace at specific mileage intervals like filters or spark plugs, but they do wear out and eventually have to be replaced. How long a set of original equipment shocks will last is anybody’s guess. Some original equipment shocks may be getting weak after only 30,000 or 40,000 miles. Struts usually last upwards of 50,000 or 60,000 miles.