I just had my rear end rebuilt, and while he was at it I wanted him to install a LS1 drive shaft. He ended up reinstalling the old steel drive shaft because he said the LS1 drive shaft pulled the yolk out an extra 1". Has anyone else had this experience?

 

The slip yoke needs to be in the tailhousing bushing 100%. It's inside but fairly easy to measure if the width is known. The back end of it can be touched from outside with a small rod. If it's not 100% in there, don't use that driveline.

The LS1 aluminum shafts are thin-walled (compared to the third gen aluminum shafts) and are internally cardboard damped. I'm not saying they're not reasonable to use for the price but you can do better with regard to strength.