Hello I have a 727 transmission and trying to find out what the switch valve does in this transmission anyhow this is what the repair manual calls this valve. This transmission got a complete rebuild new seals clutches metal sealing rings steels bushings bands torque convertor all new fluid after reinstalled but would do nothing so it was pulled back out torn back apart and the only thing I think may have been the problem is that valve called switch valve was in reversed now all of the shims and bushings still had assemble lube on them like nothing had moved so I was wondering if this valve could have been the problem it is the first valve right next to line pressure valve.
