Independent rear suspension
An Independent Rear Suspension (IRS) is an automobile suspension found in rear wheel drive automobiles and certain other powered vehicles. An IRS allows the wheels on an axle to move independent of each other, as opposed to a live axle system in which they are linked.
As the name implies, the driven wheels of the vehicle are independently sprung, either using fixed MacPherson struts or via trailing arms. Another key difference which sets an independent layout from the conventional live axle, is that the differential unit does not form part of the unsprung elements of the suspension system. Instead it is either bolted directly to the vehicle's bodyshell, or more commonly to a subframe.
The relative movement between the wheels and the differential is achieved through the use of swinging driveshafts connected via Constant Velocity (CV) joints, analogous to those used in front wheel drive vehicles.
