I have this problem for a couple weeks now and it drives me crazy. I have a vibration coming from the floor whenever throttle is applied. It seems to go away at the 70mph range but when you let off the pedal you hear a faint scraping sound for a few seconds and then when you push the pedal you will here it again for a few seconds. Universal joints were just replaced, engine cranking sounds good no pauses for a compression loss in one or more cylinders. (Used the wire next to the battery to hear cranking without the engine starting) No thumping in the air intake. I'm completely stumped. ��

My second problem may not be as big of an issue but my transmission (5r110w) is shifting very hard and slips under load or moderate acceleration. The two of these problems may be related to each other. Seems like a torque converter letting go but I have no clue, any input?

What's done to my truck:
DPF Delete
4 Inch Turbo Back
H&S Tuning
185,XXX Miles

Thank you for the help!!! ��