I've had the same issue on several occasions. It usually occurs when I'm accelerating but so far I've been unable to locate the source but I suspect that I have a boost leak.
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2007.5 6.7 auto 3500 SLT Quad Cab DRW - BADP Gen II - EGR MIA - Edge w/attitude = 2004 Suzuki XL-7 = 2001 Pathfinder SE 4x4 - 2008 Jeep Wrangler X Unlimited.