Dont know if this is in the right section but i figure i would get an answer here regardless. When im driving around 50-60mph i can see my bed bouncing up and down. I know it sounds weird, you can feel it a little but im assuming something is wrong to make it do that. Ive actually driven behind my truck (while someone else was driving it) and its noticeable and drives me nuts. Its not like the Toyota video where its scraping the back of the cab but i can see it bouncing in my mirror and it does it on any road.

At first i thought it was my Edge (some people had a similar problem becaause their edge was out of date) but I returned it to stock and still does it.

I thought it might be the clutch packs? But i dont hear any noise and it doesnt seem to shutter or anything when i turn.

I dont know, it wierd to try and describe it. It also seems to have a slight vibe/roughness when taking off from a slow roll or a stop.

It has been doing this since i bought it (used) and since then I have put on Bilstein leveling shocks, have had both my leaf springs replaced due to clunking, and new tires put on. So im kinda running out of options. I was thinking of maybe getting my driveshaft re-balanced and changing out the diff fluid and putting royal purple with a bottle of friction modifier in there.

Anyone got any ideas?

 

I've heard RP is too slick to use in the diff, even with the friction modifier.

I've also heard of people's parking brake hanging, causing a vibration.

FWIW, my bed bounces a bit as well.

 

truck details are in sig

 

Mine does that too... drove me nuts at first, but I got used to it. It is from the outward bound shocks, it's just the nature of the beast.

 

I swear it looks like the truck wants to shake the bed right of of the frame on my truck between 50 and 60 mph. The rear vibration comes in at around 56-58mph. I even rotated and balanced the tires, it took out about 40% of the vibration but I guess I will live with it. I just chalk it up to being a truck.

 

mine does the same thing, sometime it'll catch my eye when i look in the mirror, they all do it so i've heard.

 

I think all of my trucks have done this to some degree. The F150 seems to be smaller and faster movements, I guess it's just a small side effect of having a really stiff frame.
Sounds like you're going to have to learn to live with it.

 

mine does the same thing, I just get used to it.

 

It's the road.
Been driving the same route for 10 years, there is a certain section of the route where this occurs. Traffic dictates my speed.
No traffic = speed 65-75 - no bounce
Heavy traffic = speed 50-60 bed bounce
Very heavy traffic = 40 -50 no bounce

The sections of concrete are spaced such that wheel base, in conjunction with speed create a perfect rhythmic motion that is not present at higher or lower speeds.

At least this has been my experience.

 

Mine does that too.... but only at one certain time, on one certain interstate.....

I thought I was losing my mind! I was doing 75mph, on the interstate, in the desert, windows up and sunroof open (retracted into the roof) and the bed started 'bouncing'. I changed lanes. Still bouncing.

I reached up and held down the little aerodynamic metal air deflector, at the front of the sunroof, and the bed stopped bouncing. I let go, let it pop back up, started bouncing all over the place. Very weird.

Now, when I travel that certain part of the interstate, I don't open the sunroof. Problem solved.

Otherwise, I have never had any issues at any speeds or on any other roads.

 

Have you tried throwing some weight in the back and seeing if it does it still? I had a Ranger that bounced a lot so I threw sandbags back there and it helped in a big way.

The concrete is the worst part of road in my experience.

 

I've got 800 lbs of tools in the back and it still does it on certain highways.

 

Mine does it too, but I've been told that I have a tire that is out of round. It still has good tread on it so I haven't changed it out yet. I'm hoping the bounce will go away after I change my tires.

 

Never noticed that on my truck at all. Now the front end shimmy is a whole other beast. I'd highly suspect a sticky e-brake or something with the rotators for the bed bounce at certain speeds.

 

After driving get out and touch each wheel comparing temperatures. If one of the rear wheels is really hot than it is the E brake sticking. Just disassemble and clean/grease the scissor mechanism