idk either but im subscribing. my truck has a vibration between 1k - 2k and black smoke (more than normal) it only does it when under 1/2 throttle slow rev. fast rev it doesnt do it.

 

My rig vibrates at 2k due to bad u joints. but swapping to a fluid damper might help if its not in the driveline, i have seen several threads about bad harmonic dampeners

 

yeah, this one does it when parked. slow gradual climb in rpms 1000-2000 shakes the whole truck. 2k rpms it stops instantly. if i rev it fast it has black smoke. way more than a stock truck should have. (done hijacking)

 

might be normal? mine does the same thing between 1k and 2k. its done it since day one when it was stock also

 

mine only vibrates right a 2k rpms whether your driving, stopped, coasting, whatever... maybe in the flywheel/clutch/trans?

 

i noticed i have a little piece broke out of one of my fan blades 1/2 inch by 2 inches... surely that wouldnt do it??? im going to try taking the belt off to eliminate any accesories.

 

Mine just started doing the same thing starting at about 1500 rpm and up. It does it while parked in the driveway, whether the clutch is depressed or not. I was told it was the flywheel/clutch, so I dropped the tranny, replaced the pilot bearing and throw-out bearing. This had no effect. I replaced all 6 injectors since they were under warranty. Engine runs like brand new now, but still has that vibration. Could it be the fuel injector pump? I'm pretty much just guessing now. All my mechanics are scratching their heads!

 

And when either sitting still or driving, when you let off the accelerator slightly, the vibration stops completely!

 

mine has a brand new lift pump in it. it runs fine. just a little more black smoke than it should have. im thinking mine might be an injector. but i have no white smoke at start up or idle

 

Mine too, but I think it is fuel related(injectors have 160k on them). I got a company truck when it started. So I havn't had time to really drive it and/or investigate. Seems to have same symptoms. I am very interested in what you find out.

 

My vibration started after replacing all 6 injectors. Mechanic said possible low compression in one cylinder. Guess I'll have to live with it!