There are 13 replaceable bushings in a c4 auto trans. Most wear little or not at all. A few wear heavily. When having a trans rebuilt, explain to the shop that does the work that you are willing to pay for complete bushing replacement, if nescessary. Most customers shop by budget and the cheaper price is not always the best way to go. Careful measuring the bushings and changing them takes time. Time you want to pay for.
Like a chevy motor, tight bushing(bearing) clearance ensures proper pressures throughout the unit. Because a c4 auto trans is a hydraulic unit, this is critical to long life.

Good tip!

nice, which ones wear the most??

Quote:
The front pump bushing and the tail housing bushing(the one that supports the driveshaft yoke) are the 2 that wear the most. There is also a single case bushing that is prone to heavy wear. The 4th most likely is the rear sun gear bushing. This bushing is important because it keeps the rear planetary lubed.
As you get closer to the center of the trans, they wear less.
The aftermarket makes bushings that are wider to carry more load. Some even offer teflon coated front and tail bushings.
These "fancy" bushings are not really nescessary. No point in reinventing the wheel. Having all 13 in spec will greatly increase the life of the rebuild.

TTT