It is the whole truck front and rear. I also mentioned that a friend of mine has the same exact model and year it his does the same thing. He tried putting bags of sand in the back which was a total of 600lbs and he still experiences the same thing.

We were thinking maybe it needs weight in the back. I know when driving it seems to hop when hitting bumps at speeds of about 30mph, but never shakes bad like when I hit 65-70mph.

You have to see this thing, it's like I had a tire blow out. It actually scares me to hit those speeds with it. I will be visiting the dealer again and try to work this out. The Ford dealer(s) that I have gone to have really been good about trying to resolve the problem. I love the truck other than this issue, it runs great!

thanks again for the help!

 

The weight in the rear will only change the driveshaft angle (mostly the front) and it would seem to me that you would have u joint issues. You might hear a little noise while going very slowly if that was the case. I would think you problem is in the front ball joints and /or tie rod ends. Might have them check the pitman and idler arms while they are under there. Let us know what you find out and good luck

 

Have the tech at the dealer swap out all 4 tires and wheels and take it for a ride. I've seen this happen before. Not on this truck but on another Ford.

 

I'll suggest that.

I was looking at the tire pressure and noticed it recommend 75psi front and 80psi rear. Doesn't that sound high?

 

Yes. That much pressure will rattle your teeth.

 

They're E rated tires and that is the recommended pressures for maximum load. Personally I'd run pretty close to what the manufacturer states to run in the tires as that is where they perform the best. Yes the ride will be rougher but they will last longer and yield better mileage.

 

Yeah I am running them at manufactures specs.. I brought it to the dealer Friday, but have not heard back from them since.

 

Okay, I have the same problem with a 2006 F250 crew cab. But it only happens starting around 60mph...stops at around 80 mph...and on certain sections of highway that are built using sections. When I drive on certain sections of highway...I know which ones now, in the LA area, it does that unsafe jumping thing (front and rear). When I drive 600 miles of regular state highway outside of sectioned pavement on major interstates, it's smooth as silk. Same for around town driving...smooth as silk. I googled the problem and hit on this website. I saw the comment by the Ford guy so apparently they are aware of this problem. I wonder if it has something to do with the long wheelbase on short sectioned pavement. I may take mine back to the dealer too, but I'm so torn, because as you say, I love everything else about it. I also bought new tires and wheels with no change. I have the Fx4 package, but I was wondering if a custom lift would help the problem. Please post on this forum if you find out anything else.

 

Are these two trucks that are having this problem long or short bed's?

 

I've got the long bed. And I just found another forum with multiple similar complaints, including a link to make a complaint with the NHTSA. Anyone with this problem should check the link. We are not alone. [img]i/expressions/face-icon-small-smile.gif[/img]


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