Hey y'all! First time posting here.

I picked up a 1995 k1500 z71(5 speed, 180k on the od) about a month ago and have been slowly removing the little annoyances that come with an old truck like this (aka fixed ac, new brakes and rotors, rough idle etc)

Only thing that's got me scratching my head is that I can distinctly feel the drive train engage and disengage when shifting or when I let my foot off the gas and then reapply. I at first thought it was the famous gm driveshaft clunk. So I checked the rear drive shaft, lubed the splines and replaced the rear U joint and that helped a little bit but it's still pretty noticible.

This is my first time driving one of these trucks with the 5 speed so I'm not sure what's normal for them or not. My dads 94 c3500 auto has a little bit of it but it's much less pronounced than mine.

Should I be looking at the rear diff or transfer case? The truck got a new clutch from the previous owner so could they have messed somthing up there?

Thanks in advanced for the help!