I lifted my 4x2 Screw and have a driveline type of vibration between 10-30mph. It feels like you are on a washboard road at its stongest point at 25mph, then goes away after 30mph. The vibration goes away a few seconds after decelerating. No vibration when coasting at those speeds. Any ideas??? I called procomp they had no clue.

Thanks Kevin

 

How high did you lift it? What rims & tires are you using? I know that the LIFTS manufactured today are basically engineered to account for all if not most of the vibrations that LIFTS faced in the past. I do know, based on my experience, that some lift blocks (for the rear) are wedged shape to adjust for pinion angle, making them not squared as one would assume. I would read through the directions to verify that this is not mentioned in any part of the instructions. I do know from past experiences with lifted trucks, that some of the rims produced today are succeptible to pot-hole and other serious bump damage. If you might have experienced any sudden harsh jolts to one of the wheels, it is possible it might be out of round. Try rotating the tires and see if the vibration seems to move with tire rotation. LOL.

 

What tires are you running? I know that when I lifted mine...I went w/ ProComp X Terrains. They are quite knobby and I can really feel them on the road at low speeds. Maybe this is what you are feeling. Have you ever had a lifted truck before? Or better yet, have you ever had really knobby/off road tires before? This could be what you are feeling.

 

I am running bfg A/T's. So I shouldn't be feeling those.