I'll have a lot more planetary pictures soon. For now I just have some of the forward clutch drum to illustrate how they work and why most transmission rebuilds done on the 4eat skip right by a couple importan points of failure.
the forward clutch drum houses both the forward clutch and over running clutch.
Each is a stack of frictions, alternating steel plates and friction plates, plus dish plates, retaining plates, circlips, and pistons which under hydraulic pressure engage the clutches. The friction sets are easy enough remove and are what the transmission shops usually remove and replace in a rebuild. The pistons are more difficult to remove only because you have to either have the special tools from the factory or just the right set up to be able to press the spring loaded pistons in order to remove and install the circlips that retain them. The truth is you can pretty much count on your average transmission shop skipping right past this step and there are several piston seals in this trans that are prone to failure. We of course replace those seals with improved seals.
empty forward clutch drum in the press to remove the circlip retaining the forward and overrunning clutch pistons.
forward and over running clutch pistons removed and with new seals installed
note each piston has seals on both it's inner and outer
seals and grooves are covered with trans gel
forward clutch drum reassembled with new improved friction sets installed.
graphite frictions are used for both the over running clutch and forward clutch
A special retaining plate is used and the # of frictions for the forward clutch are increased.
