27 Jun 2019 Worn out shocks can make your car's springs bounce up and down more than tube, including a piston valve, a shell that acts like a cylinder, oil, and gas. the flow of oil entering the outer tube to better control the wheels. Mono-tube shocks have higher gas pressures and greater oil capacity than similarly-sized twin tubes, and have shown better performance and fade resistance 25 Nov 2019 The 1979 energy crisis, the second of two oil-price shocks in the '70s, vehicles had smaller engines and provided better fuel economy.