Could be rod bearings, but if your turbo has a radial play (side to side wobble) that means that it's on its out. When it's starved of oil and you lose the oil pressure bubble in the turbo then metal makes contact with metal, could be shaft against journal bearings, journal bearings against bore, thrust collar against thrust bearing, etc, either way it will gall and you'll lose material, metal particles then start clogging the oil passages and causing abrasion from the particulate (think sand paper), thus further decreasing the lubricity and causing more wobble, until the wobble is so bad it galls the piston rings then you lose the seal, leak oil, smoke out, then total catastropic turbo failure, as in it's spinning at 130k rpm one minute then CRUNCH it stops spinning, wheels break and lodge into the housings and the whole thing goes to hell. So if you're getting shaft wobble that usually indicates turbo is going, most likely due to oil starvation, as in clogged oil supply in most cases with these units, replace turbo and oil supply system and you might be able to save your motor. And do a full oil change, every drop you can, and clean the oil pan. Feel free to call us up for advice 800-298-8726, ask for Nick.
~tc