I NEVER have less than 1000 POUNDS in the bed of my dually.... That would be DAILY regardless of when where and how it's being driven. As stated before - the WEIGHT in the bed doesn't help the bouncing - porpoising - bad ride. The entire truck jiggles at every little bump in the road - hobby horses on concrete hiways - and just generally is a nasty riding truck.

I've driven trucks for the last 20 plus years... nothing I've ever owned has acted like this one. That would include numerous brands and models including Dodge 3/4 ton (2500's) - Suburbans - Chevys - 4X4's all....

I'll repeat the Ford Tech - two of them riding / driving the truck while I'm a passenger -- "this is the worst riding - blank - I've ever been in..." -- So there was no arguement that "something" is wrong with the truck ---- not the owners perception of what a "truck is or isn't".

If I want smooth - I'll drive the wifes 2006 650i Convertible... if I want fun -- I'll drive my 1956 Nomad (see it on Lateral-g.net) - if I want real fun - I'll drive my C5 (new corvette) based 69 Camaro Convertible... or my daughters 2006 Mustang - or my sons 2005 Hemi Magnum.

You can see by my current autos - I'm not a "brand hater"....

 

You guys must all live in states with good roads. I live in kansas and the roads are so bumpy and full of pot holes I couldn't tell if it was the truck or the road LOL.

 

Is your dogs name TOTO??

 

After looking under the truck today --- and remember this is a crew cab - long bed - dually -- the frame looks REALLY lame where the cab and bed meet... looks to me like this "necked down" frame section might be the culprit of the porpoising and jiggling. Like we do to the old Ford C frames - it needs to be "boxed".... it's most likely just not stiff enough given the length of this frame!

 

GregWeld, your truck seems to be exceptionally bad.
Most of us are just experiencing a shake between 41 and 45mph. It's bad enough that I wouldn't want to try to drink coffee but not bad enough to be dangerous.
Mine doesn't porpose on freeway blocks or wheel slap over bumps. But mine is a SRW so there's a possibility the DRW could make it worse but not as bad as you describe. I would be be taking the local Ford sales crew for a ride and telling them about the Lemon Law if mine was as bad as you describe.

I do expect the truck to ride harder than a light truck but the shake is clearly a flaw and not just a harsh 1 ton ride. I used to have a GI troup carrier. I know what that feels like.

The length of the truck should actually work in it's favor and tend to dampen out the ride.

I ordered a canopy for mine and will be interested to see if that changes the dynamics enough to dampen it. I would imagine boxing in the frame would do the same. Of course that could make the ride harsher in other ways...

 

YDM: How many miles on your rig and what configuration? And are all these fixes being footed by dealer? I assume yes. Miker67: I concur. Coming home yesterday, 2 tile saws, various bags of cement, drop cloths, stack of 20 buckets, 8 buckets of scrap tiles, levels, multiple buckets of hand tools among other things in the bed of my truck,
and traveling home on the 2nd worst freeways in the nation and I must admit that this bounce was not very noticeable by me. The ONLY time I notice it is when I notice it is when my rig is riding empty or I'm takin my rig to church on Sunday

 

Finally, they replaced my two rear tires and truck rides great now. Not smooth and I accept that because it is a truck. Can't compare this to wifes expedition

 

I have 3300 miles on my '07 F350 XLT 4x4 Auto CC LB PSD. And yes, all of the "fixes" are being covered under warranty. I haven't had anything of significant weight in the bed so I don't know if the ride will improve with additional weight. This weekend, I'm going to put a 1000 lbs. of sand bags in the bed and see how it goes.

 

Okay -- I think I might have stumbled on something with the ride - today - by accident. I've been working on an Art Morrison frame for a buddys 55 Chevy. Last night we loaded it into the back of the truck rather than the trailer (full) to take it to the powder coater.... I placed this major stiff full frame on some supporting 4X4's etc -- and strapped it down to the bed with some big 3" wide ratcheting "trucker style" straps...... This obviously stresses the bed at all 4 corners -- as well as added the boxed frame with cross supports etc...... the ride is NOTICEABLY improved --- it was like a WOW! --- Okay - it's not the WEIGHT! Two people can pick up this frame and move it - so it's not that heavy (no suspension - no motor - no tank - just bare frame).


I'm wondering if the the cab and truck bed are torqued down to spec? Tightening the bed and cab to the frame would "box" the frame.... stiffening the entire truck. I could actually feel the suspension working -- rather than the whole truck reacting to each bump... it was such a completely different "feel"! Stiff yes -- smooth no -- but no "flexing" and no jiggling after the bump - just the bump and move on --

SO -- I think I'll get the torque specs for all the cab/bed bolts to the frame -- and check and or possibly increase the torque if I think it feels 'loose'.... and see if that duplicates the feeling. This would certainly explain why some trucks feel this way and others don't seem to..... perhaps the torque spec is fine on a short bed -- or a 2 door long bed dually --- or even on the F-250's -- but might not be enough for this extra long crew cab dually model?

It costs nothing to try and might just be the culprit!

Well post after I get 'er done!

Best - Greg

 

Or instead of the bed to frame relationship it is the bed itself? Try also just putting the straps across by themselves. Maybe just stiffening up the bed will do it. That could explain why some have said that the shakes went away when they installed a canopy...

 

I had seen that comment about adding a canopy ---- which of course would add some "boxing" to the bed....


I had thought about the suggestion of just testing my therory without the frame in the bed -- and just supplying some tension to the 4 corners of the bed --- using some wood in the center so the straps could pull "up" at each corner (think "tent).... and see if that helps - or duplilcates the action of the frame. I'll be doing that this weekend.

 

Just straps diagonally, from corner to corner like an X, should do it.
I would try it myself but I don't have tie downs in the pockets and I am not going to get them because I have a canopy on order. I'm hoping that will solve the issue for me!

 

Here's another thought, I had an old 84 f250 4X4 that I bought used. it jumped all over when not loaded. It had a nice looking set of wheels and tires though I don't remember the brands. Down at the tire store one day I see another nice set of used tires and wheels at a great price. I snag em and take them home. When I put them on it was like a different truck. but the only real difference was the what I would call the set back. the geometry was completly different with how deep these wheels set on the truck. Later I put new tires on the old rims and had the same problems. Switched them to the other set and it went away. My recoletion was that there was about 1 1/2" diff with the newer set being ending up with a narrower overall footprint.

 

We have already well established that the tires and wheels are not the issue.

 

Man, you are the first to have the same EXACT problem as me... I feel the vibration/bouncing in the TRUCK itsself, not the steering wheel, not the pedals, but the entire truck is bouncing...

has anyone come up with a difinative fix for this??? so far the list of possibilities are:

- U Joints/ Carrier bearing
- Wheel balance / round
- Tie rod ends
- ball joints
- wheel bearings (not likely)
- harmonic balancer (does a diesel even have one??)
- balance driveshaft
- engine/transmission mounts

WTF???? I am going to rattle my spine out of my body...