Shocks and Struts

Struts are what you call springs surrounded by shocks (dampeners). Springs only store and do not dissipate or absorb energy.

Shocks

Shock absorbers is to damp spring oscillations but also serve the purpose of limiting excessive suspension movement. It cushion vehicles on uneven roads and keep wheels in contact with the ground.

Shocks (absorber) are made with gas or oil pistons. It takes the kinetic energy and releases it as heat.

NOTE: Rear shocks don't have an upper bearing plate

Types

• Air cylinders
• Hydraulic cylinders
• Electromagnetic
  • can store energy created

Replacement

when to replace, ytb short

• if you don't ride in bumpy terrain, your shocks will last awhile
• generally you need to replace the bearing in the top of shocks
  • then you need to replace the shocks
• the spring lasts :)
• general rule to replace after about at 120k+ miles
• check for oil leakage, bad handling, noises

Some people use shocks to modify spring rates... woah

• Softer springs will keep contact with ground longer/feel less bumbs (luxury cars)
• but might bottom out car and cause delayed control
• Harder springs for sportier cars

Sources

• https://en.wikipedia.org/wiki/Shock_absorber
• Branick Wall-Mounted Spring Compressor | DIY Strut Replacement (Ants Garage YTB)
  • For struts in the center of shocks, you can compress the spring to unscrew top and remove strut
  • Sometimes, the internal bearing on the strut cap is worn out and can be replaced
• Stuts & Shocks and cars and trucks YTB**
  • great video!
• strut removal YTB