Howdy, as I was bolting the bell housing to the block, I heard a tinney, metallic pop sound. Do you guys think its was the flex plate cracking? Are flex plates that fragile? I removed the trans to put in a new front seal. Thanks to all!

 

Did you verify that the torque converter was ALL the way into the pump before bolting up the trans? The converter should not be touching the flexplate when the trans is bolted to the block; you pull it forward about 1/4" or so after bolting up the trans to mate with the flexplate.

If you did not have the converter properly seated in the trans pump, you MAY have damaged something. I suspect the sound was more likely the trans sticking on the dowel pins and finally sliding loose to hit the block, but it is possible that you damaged either the flexplate or the drive lugs on the pump. Those are both low probability events.

Of course, if you are sure the converter was properly seated, then the sound was likely the sticking dowel pins or the converter sliding forward as the trans popped into place. Neither of those would be cause for concern.