UPDATE: I figured it out! I took it into a local deisel shop and had one of the mechanics ride with me and as soon as he heard it, he said, "It's definitely NOT your turbo. It's your wheel bearing on the front passenger side." How relieved was I to hear that! I was able to find a wheel bearing hub kit for $160 with a 5 year warranty and replaced it myself. The shop said they would charge me one hour labor and it wound up taking me about 3, but only because I put the damned dust shield on backwards and had to take it all back apart again. Oh well. Also this was the first wheel bearing hub that I ever replaced. It was very easy to do and I am VERY glad it's fixed!!!!!
04.5 GMC Sierra 2500HD SLT LLY, 4X4 CCSB, Bill's Custom Intake Stage 4, S&B Powerstack filter,LBZ MP, 4" turbo downpipe into 5" exhaust, 7" MBRP tip, EFI Live w/ dsp5, Resonator plug, PVC rerouted and plugged, level kit, 33" BFG's, all-on mod
Head Gaskets, ARP Headstuds, Full EGR Delete, Aftermarket exhaust manifold, Race Valve, CTS INSIGHT
AIR DOG II Lift Pump, Smoked tail Lights, Smoked cab clearance lights, Lift kit, and Built trans.