I recently had a new engine installed in my truck. I have had my truck for a little over a month and about 500 miles and it has started vibrating. I looked up theis problem and have found many other people with the same problem. Is anyone else having this problem or know a way to fix it. It vibrates while going between 55-75 mph, but only when my foot is not on the gas.

 

bent drive shaft, bad u joints, unballanced tires, crap stuck in tires such as mud or snow, hung rotor or dragging pads, bent rim, or unballanced tire.

 

Lots of vibration issues with the 2004 model. Take a look at all the TSB's below. Are your 20" wheels stock? If not, How long have they been on your truck? Some aftermarket wheels can cause vibration issues.
03-20-8
04-25-7
04-25-8
05-13-1
05-26-24
06-12-2
06-12-3
06-19-16

Why did you have to replace the engine already?

 

i have had my rims for over a year. no problem until after i had new engine put in.

 

My insurance replaced it because my engine, not my truck, got flooded. Not water came iside the interior.

 

maby the torque converter then, or a tranny problem, sience im guessing they attached the new motor to the old tranny, and maby they put something on wrong.

 

could it possibly be and engine mount that wasnt tightened...but if its a reoccuring problem with the 04s then i dought its an e mount
i have an 04 and i have yet to notice this vibration but i have thrown weights on my front pass tire and that was hell at 65 & up it felt like it was gonna blow up