2-3 shift slipping

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AlaskaJeff

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So my 70 Duster with a 360/727 B&M Ratchet floor shifter has a slip in the 2-3 shift when I manually run the gears and shift around 3500 RPMs. It winds up and as soon as I let off the go pedal it locks in and holds fine. The 1-2 hooks fine even at higher RPM shifts. I had a friend help adjust the bands and it didn't make any improvement. When I put it in D and let it shift by itself it seems fine. Any ideas? I've got a spare 727 that is hopefully going to be built this winter and installed at some point.
 
Jeff, the shift from 2-3 The high clutch pack does all the work as the intermediate band releases from second gear. you may be ready for a rebuild as the clutches may be worn or leaky seals.You may be experiencing what is the torqueflight 2-3 overlap when manual shifting.Even when manual shifting at part throttle at 3500 rpm the transmission is using throttle line pressure that controls the shift.At wide open governor pressure takes over throttle pressure. You may want to play with adjusting the kickdown linkage.Not saying this is the cause but worth a try.
Basically Throttle pressure and Governor pressure are fighting each other to make the shifts.That's the best way I can explain.
Weird, I have a 727 in a truck that does the same when manual up shifting but is fine when left in D.
 
Jeff, the shift from 2-3 The high clutch pack does all the work as the intermediate band releases from second gear. you may be ready for a rebuild as the clutches may be worn or leaky seals.You may be experiencing what is the torqueflight 2-3 overlap when manual shifting.Even when manual shifting at part throttle at 3500 rpm the transmission is using throttle line pressure that controls the shift.At wide open governor pressure takes over throttle pressure. You may want to play with adjusting the kickdown linkage.Not saying this is the cause but worth a try.
Basically Throttle pressure and Governor pressure are fighting each other to make the shifts.That's the best way I can explain.
Weird, I have a 727 in a truck that does the same when manual up shifting but is fine when left in D.
Manual 1st gear applies the band, D does not not weird at all. You are getting 1-2 band overlap when in shifting from manual low.
D position only uses the roller clutch.
 
I've been doing research on mismatched valve bodies to case. There is a difference in cases and valve bodies at the rear of the accumulator. Some cases have a vent hole and others do not. So I'm wondering if you have a mismatch.
 
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