keep going through u-joints bad drive shaft?

[cr125rider1988]

When i had my tranny done about a year ago the guy at the shop replaced my rear u-joint and said that my drive shaft was bad. Well a couple mounths later i blew my rear end and i took the drive shaft to a drive shaft specialist who said he couldnt find anything wrong with it. Well since a year ago i have put three more rear u-joints in it and am starting to belive the guy at the tranny shop. My drive shaft is a single drive shaft from the transfer case where it bolts on with 4 twelve point bolts and goes straight back to the rear. What could be wrong with the drive shaft that makes this happen? should i get another one from a junk yard or have one made? is this common?

[USAF-FD-NJ]

I have had the same exact issue for the past two years. Seems like every time go in for work done I'm already walking in for u-joint replacement.