accutually heres what it would be like. shocks control inbound and rebound speed, springs provide the ride hight. (note: glossy overview for simplification) if your shocks wear before your springs then your car will continue to bounce after traveling over an elevation change or bottom out in a sudden big dip/bump. if your springs go first then your car will drop in hight and the shocks will take on the extra load of carrying the car thus shortly killing the shocks.
to test bounce a corner or the front/back of the car if it stops after you stop pushing then your shocks are good if it continues to bounce then your shocks are shot. note: if your shocks are good but your spings have weakend then this doesn't apply. in most cases your shocks will wear long before the springs.
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