Oct 18, the front pump bushing presses in from the rear of the pump, but the pump has to be split to install it or remove it, the staking procedure is done from the rear with a drill bit and a punch putting the pump back together, especially the vanes and rings is an area where mistakes are made, the pump halves have to be lined up properly and then.
TEFLON PUMP BUSHING, R4 / 4L60E / R. Sonnax SB. We now offer a direct replacement for the R4, 4L60E and R pump bushing and an upgraded bushing for the 5L40E. The bushing is Teflon coated to improve cold Dimensions: 6 × 6 × 5 in. This Fits All Up TH R4 Models. and this is the most preferred by the industry professionals.
This Should be replaced evertime the pump / converter are service, or during any rebuild procedures. When Installing this bushing should be staked into position to keep it from spinning out. Often a thin coat of thread locker is used as well. Aug 04, GM fixed this problem by machining a lip in the pump to keep the bushing from moving.
I decided to buy a newer pump and just replace the pump, thus fixing the problem. Then I remembered that one of the guys in my Corvette club had taken the r4 out of his '89 Corvette and replaced it with a ZF 6 speed manual trans.