Front end rise

[SSDiv6]

Originally Posted by Ed Wright

I have always just cut the teeth from the ends of the inner tube in stock replacement bushings. Cheaper, and never bind. Bolts in the uppers long enough to bottom in the upper-inner shaft, then shortened just enough to not bind, should be able to rotate the washers under the bolt heads. My lowers right now have steel self locking nuts so I can adjsut the drag on the control arms. they should just drop from their own weight, not connected to the spindals. Been doing it like this since the Jr Stock days in the mid 1960s. Cheap and never a bind issue.

Yep, an old trick that still works; I believe either Moroso or Competition Engineering used to sell bushings that were already modified.

The difference on the OEM version of the control arm bushings is the inner sleeve is bonded to the rubber material. Therefore, it pivots on the steel sleeve and does not rotate on the rubber material.

In Polyurethane bushings, the sleeve, instead of remaining static in the bushing, also tries to turn inside the bushing when pivoting.

Polyurethane does not have the low friction and the load bearing characteristics of Teflon or Nylon thermoplastics, therefore, while pivoting, it will flex under load.

[Alan Nyhus]

Originally Posted by SSDiv6

In Polyurethane bushings, the sleeve, instead of remaining static in the bushing, also tries to turn inside the bushing when pivoting. Polyurethane does not have the low friction and the load bearing characteristics of Teflon or Nylon thermoplastics, therefore, while pivoting, it will flex under load.

There are definite differences in polyurethane control arm bushings from brand to brand. Some polyurethane compounds are 'sticky', for lack of a better term. A lube like Permatex Super Lube between the bushing and the sleeve makes a big difference.

[Eman]

Polyurethane will also dry out and crack over time. Have a Fox body with adjustable rear control arms with poly bushings. The bushings dried out and cracked into pieces and fell out.