Not necessary. It just stops the spring from rattling around a little. If you dont hear it, dont worry. If you do hear it, you still dont need it.Rover Nick said:I have an '07 40 and I need to run the included softer sping. But the supplied sping (blue, if it helps) has shrink wrap in the middle, but the stock ti spring doesn't. Is the shrink wrap neccesary? I have heard it is in previous years.