T56 input shaft bearing issues
08-28-2015, 09:50 AM
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T56 input shaft bearing issues So a couple years ago I noticed my transmission was making some noise, like a bearing was going out. At first I thought it was just the throw out bearing, but it made the noise when the clutch pedal was up instead of down. Shortly after, it completely gave out and sounded like gravel flying around in there so I tore it down and found the input shaft blew up causeing my input shaft gear spines and countershaft splines to break off.
So I replaced the worn out brass pilot bushing with a pilot bearing, new input shaft, new mainshaft, new counter shaft, new 5-6 driven gear, all new bearings, new throw out bearing, stage 2 rebuild kit with a few other parts I wanted that weren't included. Also brand new clutch, pressure plate, resurfaced flywheel. Put it all together and shifted great, didn't make a sound, everything seemed fine.
Now a few weeks ago it faintly started to make the same bad bearing noise, thinking I was just being paranoid I took it out again and it's definitely sounding like the main bearing is going out again. I've only put about 3000 miles on it since the rebuild.
So my question is, what could be causing it to keep wearing the input shaft main bearing so quickly?
So I replaced the worn out brass pilot bushing with a pilot bearing, new input shaft, new mainshaft, new counter shaft, new 5-6 driven gear, all new bearings, new throw out bearing, stage 2 rebuild kit with a few other parts I wanted that weren't included. Also brand new clutch, pressure plate, resurfaced flywheel. Put it all together and shifted great, didn't make a sound, everything seemed fine.
Now a few weeks ago it faintly started to make the same bad bearing noise, thinking I was just being paranoid I took it out again and it's definitely sounding like the main bearing is going out again. I've only put about 3000 miles on it since the rebuild.
So my question is, what could be causing it to keep wearing the input shaft main bearing so quickly?
08-28-2015, 08:28 PM
#2
Your original problem definitely sounds like a bad pilot bearing symptom got worse.
If you have poor bellhousing alignment, that could lead to damage occuring again. Checking run-out involves using the front plate of the trans. and reading the inner bearing bore in the front plate with a dial indicator.
If you have poor bellhousing alignment, that could lead to damage occuring again. Checking run-out involves using the front plate of the trans. and reading the inner bearing bore in the front plate with a dial indicator.
08-31-2015, 09:43 PM
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Watch and learn!
And here is a link to a thread which explains how to align a T56 bellhousing. Tremec states that .005 bellhousing runout is the max allowable for a T56.
http://www.pro-touring.com/threads/1...me+bellhousing
And here is a link to a thread which explains how to align a T56 bellhousing. Tremec states that .005 bellhousing runout is the max allowable for a T56.
http://www.pro-touring.com/threads/1...me+bellhousing
Last edited by TheJDMan; 08-31-2015 at 10:10 PM.
09-02-2015, 09:11 AM
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Great info! It'll be a while before I get to it but i'll make sure to align it when I put it back in.
Also i've been reading about bearing preload and shimming. I'll have to double check that as well when I get it apart. Im sure the input shaft bearing will need to be replaced. Im hoping that's the only thing at this point.
Also i've been reading about bearing preload and shimming. I'll have to double check that as well when I get it apart. Im sure the input shaft bearing will need to be replaced. Im hoping that's the only thing at this point.