Allison 6sp: Trans carnage!!!!!!

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
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ZEPHYRHILLS, FL
Bad U-joints will do that. There was a couple a few years back on this forum that had this happen. Check the engien plate closely to make sure it isn't cracked around the mounting bolts when you pull it down(you will have to pull the flex plate off to check it). I think the one here a year or 2 ago was lifted about like this one is as well.
 

SmokeShow

Well-known member
Nov 30, 2006
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Lawrenceburg, KY
Mine did that but closer to the mounting surface & got the rear engine cover. Bad unjoints lead to ever-so-slightly warped driveshaft which caused my issue. Not before it took out two rear extensions (first one happened on interstate & is why I have a built trans now) and the bell & rear cover. :eek:

New joints & shaft & she's smooth as glass again. :)