A few months back I had asked if anyone had heard this whooping noise that my truck was making. A few said it could be a valve issue, another thought it may be an injector etc, etc.
I finally took it into the Dealership and had them tear in to it and this is what they found..... #1, The Roller Lifter on the last cam lobe (firewall side of cam) had the wheel lock up and wore a channel / groove in the cam lobe causing the exhaust valves to not work for that cylinder. #2, the "Y-Pipe" had a crack in it causing some extra noise and soot on the firewall. #3, The Turbo's shaft had some slack / free-play up & down in it, so I replaced the Turbo so I would not have trouble with it down the road.
So everyone who thought it was a Valve train problem you were right! But who has ever heard of a Roller Lifter wheel locking up? Anything is possible with mechanical parts... I did buy the truck used ant the Mechanics said it may have been run low on oil at some time.
Below are a few pics of my truck and a couple of cam lobe pics in the motor. I will post a few of the Cam by its self that should be easier to see the groove.
Thanks again for all the ideas!! I am glad to have my truck back and running like it should!!