Shock Bushings and Strut Mounts: When They Break
Shock Bushings and Strut Mounts: When They Break
We heard from a customer who had relatively new Bilstein shocks: "Left shock mounting rubber at the top of the shock has broken." That's not covered by warranty because what the customer needs now is new upper mounting hardware. "It most likely broke because it was over torqued on installation," our Bilstein representative told us. "He only needs to use 34 ft lbs of torque. He/his shop probably used OE torque specs which are much too high, sometimes almost double." We thought this was worth passing along to you. This phenomenon is actually confirmed by KYB's technical tips pages as well.
Aftermarket bushings are made from polyurethane that's different from the material used on factory bushings, and they don't require as much torque. If you use too much torque at installation, your mounting rubbers will be stressed. If a mounting rubber breaks, your shock is probably still fine but you will definitely need a new mounting kit. When they break you will know it because you will hear a lot of rattle and pop on the road.
Strut mounts, in front, are designed differently but they do basically the same thing as strut mounts: reduce vibration and noise. They are made of the same stuff. Strut mounts are a normal wear and tear item, so you should of course replace your mounts when you change struts. The labor costs just for changing the mounts can be high depending on the location of a worn-out mount. Check out the Shockwarehouse knowledge base article on Strut Mounts.
If you have installed shock mounts before, you know that you need a special tool to hold the interior of the shock stationary while you tighten the nut. Our chief mechanic here at Shockwarehouse advises: "If you don't know how to tighten it, you don't know what you're doing, so stop."
Good old Popular Mechanics has a decent article on replacing shocks.
Strut mounts
Aftermarket bushings are made from polyurethane that's different from the material used on factory bushings, and they don't require as much torque. If you use too much torque at installation, your mounting rubbers will be stressed. If a mounting rubber breaks, your shock is probably still fine but you will definitely need a new mounting kit. When they break you will know it because you will hear a lot of rattle and pop on the road.
Strut mounts, in front, are designed differently but they do basically the same thing as strut mounts: reduce vibration and noise. They are made of the same stuff. Strut mounts are a normal wear and tear item, so you should of course replace your mounts when you change struts. The labor costs just for changing the mounts can be high depending on the location of a worn-out mount. Check out the Shockwarehouse knowledge base article on Strut Mounts.
If you have installed shock mounts before, you know that you need a special tool to hold the interior of the shock stationary while you tighten the nut. Our chief mechanic here at Shockwarehouse advises: "If you don't know how to tighten it, you don't know what you're doing, so stop."
Good old Popular Mechanics has a decent article on replacing shocks.
Strut mounts