How Do You Find A Car Suspension Transfer Function (Frequency Response Function)?
You need to develop the differential equations that govern the motion of the vehicle mass which depends on the suspension parameters such as the spring constant and damping. The equation should look something like this. Where xdot is the first time derivative of x, and x^2dot is the second time derivative of x. M*x^2dot + c*xdot + kx = f(t) where M is mass supported by suspension, c is the damping constant, and k is the spring constant, and f(t) is the input force as a function of time. To get the transfer function take the Laplace transform of this equation, plug in the initial conditions, and solve it for system output/input. So in this case it would be something like X(s)/F(s) = 1/(M*s^2 + c*s + k) but may be slightly different. Do some reading on your own as well to help figure this out, I cannot give you a complete explanation on this forum and you should learn how to do this as it is very important in analyzing control systems.
