Pulled type 13 driveshaft out of my 1990 740 GL (after marking for future reassembly), had shop remove old bearing and install new one (not genuine Volvo bc backordered, haven’t yet confirmed it’s OEM). Reinstalled shaft, observing my markings. took for slow drive around block (<30 MPH). No detectable driveline vibration. Smelled burning when I got out of the car. Looked under to see SMOKE wafting out from the cavity where bearing sits. Lubricated, loosened ever so slightly the flange screws holding the bearing housing to mounting plate, then pressed my luck and went for 50 MPH test drive. Still no detectable driveline vibrations, but upon stopping to check I smelled the bearing cooking again, though this time I saw no smoke. Limped home at 30 MPH, but when I got back home and checked again, there was neither smell nor smoke. Am I misaligned after all? (Found no helpful stampings on either section of driveshaft to guide me.) Or could it be that the rubber from the old housing (which got shredded/liquified and sprayed everywhere under there; don’t ask, don’t know) is getting burnt off somehow? Thanks for any wisdom, gentlemen. ATTN: @hoonk (my mentor @lev recommended I tag you)

 

As long as no more burnt smell or smoke or drivability issues, I'd call it good! I can't see how you can missalign that anyway. Sometimes, well, things happen we can't explain... I'd like to know what causes what you had but I can live without it...

 

So....

....weird hot smell is back. Not a burning, like oil on the manifold or the like, more like hot metal. Maybe electrical? I did have to install a new butt connector when a spliced wire (coming from the shift lever above?) came apart when pulling out the drive shaft...

No smoke, no driveline vibration, even at high speeds, but now it seems that after driving at high speeds for 30 minutes or more, the “hot smell” can be detected.

....Is there anything about a new center bearing (and housing) that would need to be “broken in”? Do I just need to keep lubricating?…

 

Bearing like that should not be burning or in need of lubrication! I don't know what you are smelling, could be something unrelated... "Hot metal", hmm, no idea...