Hello looking for some input here. I had a 2001 f150 super crew with the 5.4 triton. When I took off with it from a stop it would be like I was running over rumple strips.

Well I got rid of that and got me a 2002 exactly the same just lower mileage. I've had it a little under a year now and this truck is doing the same thing. I've checked it out but can't seem to figure out what it is.

Anyone had this issue and know what it is?

 

A u-joint that is running dry and getting ready to go south can do this.

 

Check the ujoints even tho I just replaced them they are good. It is worse when I am towing a trailer. Still can't figure it out I just replaced the axel baring thinking maybe that was it and it's not.

 

If you load the engine in gear with the brakes applied does it do it then ?
Did you when replacing the u joints change the position of the slip yoke causing the joints to be out of phase?
Does your vehicle have 2 or 3 u joints and did you replace all of them?