You answered your own question, look at what you quoted me. "I dont think it was greased much before I got it" and "they are tight as can be and lubed every oil change"-reffering to what I do now.


My OP reffered to strictly the splined section of the DS, where anyone got confused and started talking u-joints, I dont know, maybe because I mention checking them? I grease the u-joints at every oil change, and the grease fittings for the splines. The previous owner probably never greased anything. Everytime I grease the u-joints, I make sure I got grease from all 4 caps.

Now could they still be bad? Maybe. But with that much slop in the splines, I aint waisting time putting new ones in, until I get a new/used front shaft.

 

Only you don't really know if the u-joints are perfectly fine, based on the way you described checking them. Just because you lube them properly now doesn't mean damage wasn't done previously.

But back to the "flex" part of your OP. Are you saying you can bend the propshaft 1/8" along it's axis? Or that you can rotate the two parts 1/8" in opposite directions from each other? If the former, then that's bad. If the latter, some play is normal, but 1/8" may be slightly on the excessive side, but probably not the source of the vibration.

 

Yes, all the play was along the center axis at the splines, no slop when twisting either direction. I picked up a used one at a yard for $75(that i got to pick and pull,made sure it's tight) and slapped some new u-joints in it.

FYI- not a big fan of autozone parts, but their u-joints have the grease fittings in one of the bearing caps. I was having to disconnect the front DS at the t-case to be able to get to the zerk on the old one.