I don't think Peter's turbos have wastegates, do they? I know for sure he doesn't have an ECM or any DTC's to set and definitely no SES lights....
I hardly have any smoke when running biodiesel, but when I switch back to #2, the black smoke comes back. So switching to bio might work, if it's available to you.
Casey
1995 K1500 Tahoe 2 door, 6.5LTD, 4L80E, NP241, 3.42's, 285/75R16 BFG K02's; 1997 506 block; Kennedy OPS harness, gauges, Quick Heat plugs, and TD-Max chip; Dtech FSD on FSD Cooler; vacuum pump deleted, HX35 turbo, Turbo Master, 3.5" Kennedy exhaust, F code intake; dual t/stats, HO water pump, Champion radiator; Racor fuel filter