Broken 241 extension housing

[1979jimmy350]

What would cause the extension housing to crack off a 241 transfers case? My buddy just changed the ujoints in his 91 because the rear ones failed after he changed them he drove it around the block and a bunch of noise came from the drive line and when he reomved the drive shaft the extension housing came off with it. I just don't want to put every thing back together for him and have it happen again. Luckly i had a extra extensionhouseing from a 233 transfer case i was suprised that they fit and were even the same gm part number

 

[btolenti]

It sounds like when the u-joint initially went bad it might vibrated enough to crack the extension housing. It eventually failed after some use (coincidentally after the u-joints were changed)????

Apparently this is common???

http://coloradok5.com/forums/showthread.php?t=148944