It is a 2002 F150, 5.4L V8, 4x4, regular cab, former fleet with 125445.7 miles on it. The tires are Cooper Discoverer ATR. I washed it the other day, and took it for a spin around the block. Not that long into the drive, the truck felt like I was going over really rough terrain. I thought I was driving with a flat tire! I drove home right away, and it did seem to mellow out a bit before arriving. The next day, upon returning from another spin, it was much better but there was still this general shaking. The vibration doesn’t come from the steering wheel. I took a friend, who has ridden in this truck before, for a test ride and he noticed it too. He seemed to think I should have my tires rebalanced, and see if that works. The Haynes Manual for it said it could be ether the ball joints, wheel bearings, or the suspension. I checked the tires air pressure, and they were all low. I put in as close to the called for PSI as I could with the air pump I had, leaving it a little under for tire heat up. It was still rough.

Some more info. It is having rust issues on the underside, and the truck box is loaded with tools. Not long before the problem started on that drive, I did swerve left and right a bit to shake any trapped water lose. The rear passenger side wheel has a leaky oil seal too. I looked at the rubber covers to the CV Joints, and none of them look to have been leaking. All the exposed U Joints were tight, but rusty. I do have a habit of using the rear tires to climb into the bed of the truck, and those tires were under inflated. The truck makes a squeaking noise when I turn right. The truck is not my only vehicle, so the F150 has not been used since this happened.

I never done this before, so any input is welcome. Tips on how to check on the status of the parts, tips on how to change them out if necessary, pics, videos, and diagrams very welcome.

 

Maybe a COP? Check for stored codes.

 

More info on the vibration please. What speed does it start? Does it vibrate at idle? Does it stop at a certain speed (get up to 70mph). Does the intensity and speed of the vibration fluctuate with increased speed?

 

If it's a fleet truck, I would replace the ball joints and tie rod ends. They've probably been overlooked and ignored for a while seeing as it's a fleet truck. And at that many miles, it's probably a good time to change them anyways. How are the tread on the tires? Are they still good?

 

Tread seems fine, no bars showing. No uneven wear from what I could see.

It’s a little hard to say, but I would say it starts around 2o-30mph.

I would say no more vibrating at idle then before.

I didn’t get it up to 70 that day, but at around 55-60 I thought I detected it smoothing out.

I hope that helps, going off of memory from last week. Family is here because of Thanksgiving, so today I had a lot to do.

Ball Joints
http://www.flickr.com/photos/62362374@N05/11071955663/

http://www.flickr.com/photos/62362374@N05/11071910044/

Rear Oil
http://www.flickr.com/photos/62362374@N05/10079974393/

 

Ball joints have been replaced before. Fill them with grease in your free time. Will ensure they last longer.

If you don't notice it until 30mph and it stops after 60 my guess is a COP is going bad. You will need someone that can read MODE $6 data and see which cylinder is misfiring. Unless you hammer on it and can get a code.

Otherwise you could get your tires balanced, it's usually pretty cheap.

Happy Thanksgiving!

 

Possible U joint failure.

 

Seeing how you just washed it, I have to ask... Did you wash the engine or get it wet? I had a coil pack get wet once, and my truck would do the same thing, it was the engine misfiring... I too an air hose to all the coil packs and let the hood up with the engine in the sun for a couple hours... Fixed the problem... gotta keep them COP's DRY!!!