I have an 04 that for awhile has had a bounce going down the road. Has anyone else had these problems. I put 4 inch blocks in the rear and new shocks and I was hoping the new shocks would get rid of the bounce. It has not.

I am going to go and have my tires re balanced, is it possible U joints could cause this?

 

I would check to see if the bed cross members are rusted out. I know mine are.
Only fix there is new cross member or a new bed.

 

I retitled the thread. It is not my actual bed, it is just bouncing from the rear.

 

Tire separating.

 

You might want to check out your rear brakes. Does it happen when you are just driving or when you are braking?

 

Only when driving, between 45 to 50 mph

 

this just suddenly start? a bunch of folks are reporting similar issues at the same speed on new trucks.. 08/09/10/11/12's same speed.. so far no one has found the fix..

Sam

 

I think it is the tires. Idk though, my stock rancho fx4 shocks had 128 thousand on them and I just figured it was them. Replaced with Bilsteins and it is still there. Like I said I am going to go by and get my tires re balanced on Monday and see if it goes away. If not I really don't know where to go from there. It was doing it prior to me installing the leveling kit/ 350 blocks in the rear end, and is still doing it. I am running 285/75/16 BFG AT/KOs.

Under acceleration it does not bounce, only when I am coasting between 45 to 50 does it seem to bounce. It is noticeable too, though it does not seem to be getting any worse or better.

 

Start by placing the rear tires on the front. If the problem follows the tires you found the area where the problem is. If it doesn’t follow with the tires start examining the brakes and parking brakes. If it has disc rears I’ll bet the caliper slider pins have frozen. Replace or clean and apply anti-seize it everything. Check the brake backing plates too they are known to rot and fall apart, especially if you live in the rust belt.

 

Is the bouncing possibly the road your driving on? My '01 CCLB has a few spots on the highway where the concrete seams must line up just right and get me bouncin' a bit. I change lanes and it goes away. Speed is not a factor in the 50-75 range anyway. I found if I just stay in a different lane in those particular sections of hwy, no bounce.
If it isnt the road, check the TSB's. I think Ford had one out where they added degree shims to the rear end to help with spring wrap adversly changing the pinion angle.