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Bed Bounce?

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Old Jan 3, 2009 | 05:31 PM
  #16  
SIK-06's Avatar
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From: Glendale, AZ
try getting your tires rotated and balanced that made mine go away!
 
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Old Jan 3, 2009 | 07:43 PM
  #17  
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From: Little Rock, Arkansas
yeah, my brakes and rotors are in really bad shape, that might help out
 
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Old Jan 11, 2009 | 05:43 PM
  #18  
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From: TX
My truck's bed bounces around 50 mph as well.
As best as I can figure, that speed produces the natural resonance of the rear suspension, causing it to bounce and twist with the slightest bump or unevenness in the road.

If you dont know what I'm talking about as far as the resonance thing, it is similar to what happened to the Tocama Bridge. Check out the video http://www.youtube.com/watch?v=P0Fi1VcbpAI...look familiar?

However, because we are dealing with a truck bed and not thousands of tons of steel and concrete, I dont think there is anything to worry about... I've never heard of anyone's bed flying off their f150 have you? It's just physics ya'll.
 
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Old Jan 11, 2009 | 06:17 PM
  #19  
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From: BURBANK ILL
Originally Posted by DaMoose81
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At first i thought it was my Edge (some people had a similar problem becaause their edge was out of date) but I returned it to stock and still does it.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 have the slight vibe/roughness on take off from a stop light Since the temps dropped below 20 degrees But i have no rattle when i start the truck It seems like the warmer it gets i get no vibes and i get rattle on start up I only have 18xxx miles
 
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Old Jan 12, 2009 | 08:24 PM
  #20  
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From: Ct.
I never noticed the bed moving but, maybe I'm distracted by my tonneau cover flapping around!!
 
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Old Jan 12, 2009 | 09:21 PM
  #21  
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From: Bowling Green, Ky
I agree with others, just have to deal with it. Weekend before last I had my tires balanced and rotated. Before doing so, if felt like was riding in a tater wagon. Bed bounced so bad that the whole truck shook. After I had them balanced, the truck rode so smooth that I thought I was in a new truck. No bed bounce at all, not even the steering wheel shimmy. But 2 days after, the bounce is back. Like others it seems to do this around 50mph. I think these trucks are VERY sensitive to what type of tires are on them. Or maybe tires just have to be balanced perfectly. Its just wierd that my truck rode so good after my balance and in 2 days it rides like crap again.

So what is a person to do? I've tried everything.........just deal with it.
 
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Old Jan 13, 2009 | 01:09 AM
  #22  
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From: Oregon
Mine bounces around 60-65 mph. It's fine above or below that. It did this with stock tires, stock shocks. It did it with new shocks. It does it with new shocks and new tires. Starting to get irritated but I don't think there is much that can be done. I suppose it could be brakes or driveshaft but I doubt it. Seems like the stiff frame just resonates and shakes at a certain speed. I may have my wife drive it around and I'll drive the lowered Jetta behind and see what all is bouncing...
 
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Old Jan 13, 2009 | 09:40 AM
  #23  
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i just got an '06 and i notice it around 54-60ish, the first time i noticed it i thought it was going to throw the bed off the truck, but above and below its just fine. you get used to it and is not bad all the time.
 
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Old Jan 13, 2009 | 12:09 PM
  #24  
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From: NorΩCal - East Bay
It was pretty bad on my truck as well but two things really helped out:
First, was after market shocks (Bilsteins in my case).
Second was tire pressure. When gas was going through the roof, I aired up my Nitto's to about 48psi or so. That's when things got real crazy!! I've since aired way down and it has really made a big difference.
 
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Old Jan 13, 2009 | 01:20 PM
  #25  
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ill check my air pressure....mine is just coming from the LEFT side, right side is fine, 52-57mph the left side looks like its about to come off the truck.
 
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Old Jan 13, 2009 | 06:29 PM
  #26  
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From: Oregon
Left side as well. I've been letting air out (now at 35 psi with 35's), trying to finding a good balance for good tire contact / even wear.
 
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Old Jan 13, 2009 | 07:11 PM
  #27  
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From: Bowling Green, Ky
Yea mine is worse on the left side too. Seems to be the same side on all these trucks. I too have the Bilsteins, but it didn't help much at all. As far as tire pressure goes, the lower the tire pressure the better they ride. Only thing that concerns me is that most people on this site use at least 40 psi. I have the Nitto's Grapplers(295/70/17) and usually I run them at 40psi, but i've been told by several on here that I shouldn't run them under 40 because of fast tread wear. But I'm going to try running them at 35 and just see. If they wear quick, fine. That way it gives me a pretty good excuse to get me some MTZ's
 
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Old Jan 13, 2009 | 09:14 PM
  #28  
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this was big issue in 2005 and 2006 when we bought our f150's

has to do with the way the cab and body mounted

many were seeing the bed move and found it waS the cab

there were several who had movement when towing, for some it was the resetting of angle of truck with a load

some had tire or drive shaft balance, but as a whole even after making tire and driveshaft balancing they still had the movement, i believe most just live with it

I thnk most just accepted the motion and moved to other problems

yu might do a search for bed movement.
 
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Old Jan 21, 2009 | 04:15 PM
  #29  
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notice that my left side cab/bed is not ligned up, the bed is in farther then the cab and the right cab/bed is ligned up striaght, is this the same on others? found this from another forum...
Yes, there is a device on the drivers side rear corner, and yes, it is used as a harmonic balancer of sorts. I had to remove mine when I installed a Reese hitch, as it's bracketry interfered with the hitches side mounts to frame. It has been over 3500 miles since, and my truck does not bounce at all. No vibration, no bounce.
 
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