I found the self-lubricating Turcite/Delrin material totally silenced the squeaky OEM pivot cup and also stopped the truck from diving at the end of a turn, instead the hanger pivots in line with the rigid pivot cup. So this helped eliminate a bit of wheel bite I was seeing with the softer OEM pivot cup. Currently I have over a year of pumping use on these and no wear visible. Think of Turcite as a cross between Delrin and Teflon, the strength of Delrin with the self-lubricating properties of Teflon.   (12/70)