Trans Experts??

I have a Getrag 209 in a '95 GMC 4x4. A local guy rebuilt it after it ate up 1st 2nd & 3rd. Now it jumps out if 3rd when you let off the gas, the guy is
wondering where to go next. He put new gears and syncros in, one of his trans experts thinks either it's in the shifter (never did it before) or the syncro hub is in backwards. Anybody have a clue? I know "DOC" & "TRANSSURGEON" are pretty sharp on this stuff.......
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Al Bosch wrote:

I'm not sure that you could get the syncho hub in backwards on the transmission, you would probably end up not being able to fully install other components. I'd lean more towards too much endplay somewhere on the mainshaft. Any excessive movement can cause the mainshaft to move back and forth, especially as you either come off or on the gas. It may be that when you come off the gas, the mainshaft is moving enough to pop the trans out of third.
Ian
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The endplay was in the back of my mind. I ran into that on Muncie 4 speeds in my younger days ......

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I'd lay odds that:
A snap ring either broke, or wasn't totally seated in the groove when installed.
Not a derogatory remark, been there. Done that!
That's what's causing the end play Ian spoke of.
Refinish King

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