Ok, so the frontend in my truck came out of a 74 K20. I have a spare set of shafts out of a 73 K20. Found out tonight that one of my ujoints was shot in the drivers side, so White-Rhyno took my front axle apart. Well, the shaft that came out was WAY skinnier than the spare 73 shaft. We figured, cool, bigger shaft... put it in, and it won't turn??? What is up w/ this??? I thought that a D44 shaft was a D44 shaft???