Bimmerfest - BMW Forums - View Single Post - Broken rear spring, Removing rear shelf to get to strut
View Single Post
Old 01-30-2013, 09:43 AM
Fudman's Avatar
Fudman Fudman is offline
Officially Welcomed to the 'Fest
Location: Sudbury, MA
Join Date: Apr 2007
Posts: 6,823
Mein Auto: '02 530i Sport auto
I cannot see your pictures (blocked at work) but it sounds like you have broken a coil spring. Yes? This is a highly unlikely event but not impossible (I've broken a leaf spring before on my previous Explorer). Anyway, if your spring is indeed broken, it is definitely the cause of your shaking problem. Here is why: The wheel is connected to the car by the suspension links, strut (damper) & spring. The linkage controls the direction(up/down) of wheel motion while maintaining the wheel position relative to the road (slight camber). The springs and the strut control the initial position of the wheel and dampen its subsequent movement while still allowing it to move up & down to accomodate road surface irregularities. The frequency at which something vibrates is directly proportional to stiffness and mass. Change the stiffness and you will change the frequency for vibration. A broken spring greatly changes (reduces) the stiffness of that suspension system. Hence, the frequency of your suspension system is lowered. When the driving conditions match that frequency, significant vibrations occur. That shaking (feedback from wheel vibration) is the direct result of the stiffness reduction caused by the broken spring coil.
Reply With Quote