Extended shackles give extra rear lift without changing the springs, so they are useful when the vehicle is sitting low at the back or when extra clearance is needed for larger tyres.

They help level the vehicle after adding accessories such as a canopy, drawers or tools, and can improve articulation by allowing the leaf springs more movement on rough ground. They are also a simple way to raise the rear when the front has already been lifted.

They should be fitted when the rear suspension sags under load, when the vehicle sits nose-down after a front lift, or when more clearance is needed for off-road use. They are also a good option when the original shackles are worn or seized and need replacing anyway.