When should you need to replace your shocks and struts on a 2004 chevy trailblazer

Depending on the type of driving you do, determines how long shocks or struts will last. Todays shock/struts use a nitrogen gas over oil system, meaning the unit does not need to be leaking hydraulic fluid to be bad.When it has lost its nitrogen gas, it is no longer able to hold the tire firm to the road, allowing increase in tire wear and a poor ride. As the shock ages the seals will deterioate enough to allow the gas to leak and show no signs of oil. Rule of them is 40000 to 50000 for a car with stop and go driving, and 75000 to 80000 for one with highway miles. Depending on the type of driving you do, determines how long shocks or struts will last. Todays shock/struts use a nitrogen gas over oil system, meaning the unit does not need to be leaking hydraulic fluid to be bad.When it has lost its nitrogen gas, it is no longer able to hold the tire firm to the road, allowing increase in tire wear and a poor ride. As the shock ages the seals will deterioate enough to allow the gas to leak and show no signs of oil. Rule of them is 40000 to 50000 for a car with stop and go driving, and 75000 to 80000 for one with highway miles.