Variable rate bushing for stabilizer bar

A vehicle suspension system comprising:

• a stabilizer bar connected to a vehicle wheel;
• a vehicle frame;
• and
• at least one bushing made of rubber positioned about said stabilizer bar including at least one passive structure, said passive structure extending along a length of said bushing and interacting with said stabilizer bar to vary a level of stiffness of said stabilizer bar, said stabilizer bar secured to said frame by a mounting bracket positioned over said at least one bushing.

The method for controlling a rate of a stabilizer bar of a vehicle suspension system comprising the steps of:

• mounting a stabilizer bar to a vehicle with a bushing having a passing structure to vary a level of stiffness from a first level in response to initial twist and then to a higher level in response to additional twist;
• axially twisting said stabilizer bar;
• and
• varying a level of stiffness of said stabilizer bar from said lower level during initial twist to said higher lever after said initial twist.