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Input shaft help/options on 84 tranny

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Old 03-18-2017, 11:51 PM
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checkmate1996
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Default Input shaft help/options on 84 tranny

So my rebuilder says when he spins the input shaft bearing freehand he can feel a slight "sandpaper" feeling to the bearing. This tranny only has 34k miles on it. I went out to 928intl and a new one is 650$.

How concerned should I be? Are there alternate parts or sources?

thanks for any intel!
Old 03-19-2017, 02:08 PM
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James Bailey
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If it was a $35 wheel bearing what would you do ? And wheel bearings are easy to go back in and change. So now that your rebuilder questions the bearing if you do not replace it you pretty much void any warranty !
Old 03-19-2017, 02:21 PM
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hacker-pschorr
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Originally Posted by checkmate1996
This tranny only has 34k miles on it.
New as in all original from Porsche with 34k mile son it or 34k miles since it was last rebuilt?
Old 03-19-2017, 03:04 PM
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GregBBRD
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Originally Posted by checkmate1996
So my rebuilder says when he spins the input shaft bearing freehand he can feel a slight "sandpaper" feeling to the bearing. This tranny only has 34k miles on it. I went out to 928intl and a new one is 650$.

How concerned should I be? Are there alternate parts or sources?

thanks for any intel!
It's common to have used ball bearings "feel" bad....one tiny piece of grit makes them feel terrible. And dry bearings also feel terrible. Clean with some type of spray cleaner and blow dry...multiple times. Avoid the "cool" noise that blowing a bearing and accelerating the outer race makes....this ruins a dry bearing!

When clean, lube it with WD40 (or any thin oil) and see how it feels.

It's a simple matter to inspect the ***** and the races for condition. A flashlight held so one can see the race, ispecting from each side, and looking at both the inner and outer race, while slowly rotating the bearing, will show any flaws.

If not able to see every little detail, push out the plastic cage that holds the *****, move the ***** all the way to one side (do not disassemble) and you can see everything. Tiny pits from metal running through the bearing are normal....you are looking for places where the entire surface of the races is coming off.

If it is bad, there is only one choice....replace it.

When the early bearing was over $600 and the '85/'86 bearing was $55, I machined the cases to accept the cheaper, larger, better bearing. While the '85/'86 bearing has "caught up" in price (still isn't $650), the cost of the machining plus the bearing gets you to about the same $650 price. I now machine the cases not to be cheaper, but to use the bigger, better bearing.
Old 03-19-2017, 03:31 PM
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James Bailey
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the master has spoken ..... you may as well close this thread now
Old 03-19-2017, 04:45 PM
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checkmate1996
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Thanks for the responses. I am passing the info on. Btw this is an original 34k tranny. Car has sat garaged most of its life. I have known the owner for the past 18 years and we know most of the history from there. If the bearing needs replaced I will but that bearing cost is pretty big pill to swallow....
Old 03-19-2017, 05:26 PM
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GregBBRD
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Originally Posted by checkmate1996
Thanks for the responses. I am passing the info on. Btw this is an original 34k tranny. Car has sat garaged most of its life. I have known the owner for the past 18 years and we know most of the history from there. If the bearing needs replaced I will but that bearing cost is pretty big pill to swallow....
Why is a transmission with 34k apart?
Old 03-19-2017, 05:37 PM
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from what i gather, someone got in to it to fix second (for some reason) and did a crap job.
Old 03-19-2017, 06:30 PM
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checkmate1996
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Yeah what Jake said... someone rode second gear hard and synchro and dog teeth were shot. They tried just replacing synchro and did it incorrectly. It's been pretty much sitting in this condition for 15-16 years...
Old 03-19-2017, 08:51 PM
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GregBBRD
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Originally Posted by checkmate1996
Yeah what Jake said... someone rode second gear hard and synchro and dog teeth were shot. They tried just replacing synchro and did it incorrectly. It's been pretty much sitting in this condition for 15-16 years...

Mongo drive Porsche.

Very doubtful that the input shaft bearing would be bad at 35K, BTW.
Old 03-20-2017, 08:52 PM
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checkmate1996
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my rebuilder took the bearing to a specialist and he said the bearing is behaving as expected. Crisis averted!



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