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Discussion Starter #1
Just wondering what the output play should be on a TH350. It's not specifically mentioned in the Ron Sessions book, only the input shaft play. Thanks.
 

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I dont know if there should be any. Normally play in the output shaft is signs of a bad tailshaft bushing isn't it? I would imagine that play in the output shaft combined with that swinging driveshaft would cause some serious vibrations.

But I dont really know much about it so I guess wait for a more educated answer :).
 

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You defently want as little as possible. Its probably not a good idea to get much more than 1/4" or 3/8". How much are you dealing now?

Stroke of Genius
 

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If you are talking about end play it is measured from the input shaft only.
If the transmission is positioned so the input shaft is pointed up the output shaft has to be towards the back of the case.
The input shaft is now pulled upwards and the result is end play.
 

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Discussion Starter #5
Ok I understand what you're saying about measuring input play. I thought I heard that the output shaft play could be separately measured from the back of the transmission. I'm half way thru assembling the transmission...I haven't installed the input shaft yet and just happened to notice some play (back and forth) in the out put shaft. Perhaps this is normal and maybe why it was not mentioned in the book.
 

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Without the transmission assembled there will be movement.
Some other transmissions have output shaft adjustments.
Not the TH350.
 

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IF there is too much end play of the input shaft after the pump is installed ....... there are shims that can be installed under the bearing on the out put shaft to tighten up the end play of the tranny at the input shaft.

I have never checked the end play of the output shaft by it's self as stu is pointing out here
 

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The Ron Sessions T-400 reference calls for .003 - .019 rear end-play. On my 400 I found .030 during disassembly.

As you probably already know, selective thrust washers can be had to make up the difference, you have to mike the selective washer you have after removing the planetary gear assembly from the case.

I wouldn't imagine the 350 would be much different than a 400, at least on the point of having/not having or requiring a certain amount of end-play.
 

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Discussion Starter #9 (Edited)
Thanks all, I did measure the selective thrust washer and endplay when I disassembled the transmission so hopefully when I put it all together the final endplay will be close to ideal. I think I mixed up the endplay measurement procedures for the TH400 with the TH350...anyway the issue is much clearer now.
 

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End play on a TH350 is set by the selective washer on the pump.
As Crosley stated if there is excessive clearance there are steel shims available to be placed under the case output shaft bearing.
 

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stu, thanks for clearing up the info.

the shims under the rear bearing of the output shaft ring gear of the t-350 is used when the clearance at the pump is too much.

When I was first hired at my current employer I built 10 - 12 t-350 a week. I used a .030 shim under all of the output shafts

There are other methods to tighten things up in the t-350 best left to the experinced builder
 
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