Many may think that the only purpose of shock absorbers is to give the vehicle's riders a comfortable, smoothe ride. However, providing a smoothe ride is really just an added benefit of their real purpose; keeping the tires on the road. As Newton taught us, forces act in equal and opposite directions. During braking the tires endure additional force and can come off the road, due to that force. If a tire is not making contact with the roadway while braking, then that tire is not adding to the force needed to stop the vehicle. This is where the shocks come into play. They keep that tire on the road!!! While changing my rear brake pads, I noticed hydraulic fluid had leaked all over the rear passengers' side shock absorber. This is no good and a definite sign that the shock had failed. You can notice the fluid on the old shock in the image below. I replaced the original shocks, which had already endured over 200k miles of wear, with new Monroe GAS-MAGNUM Light Truck Shock Absorbers purchased at Advance Auto Parts.