I bought a used 2006 f350 king ranch 4 x 4, at 40mph I get a vibration, shaking/bouncing, ive checked drive train put in front sway bar bushing, and replaced a tie rod end, and today I bought 6 new tires had them mounted and balanced, and I still have the shaking,vibration, bouncing, when I let off the gas it goes away, but as I resume the fuel it come back. I have no engine codes, so im out of ideas, please help, am I looking at something major, or overlooking something.

 

 

only noticed it on speeds.

 

Is there a steering damper that is misbehaving?

 

at the risk of being dumb, where do I find that steering damper, and would that shake the whole truck?

 

The more info you can provide the better.
Maybe if we ask some addl questions it might help.
Since you had the tires replaced, and balanced ,we would hope if there were any bent rims that would have been picked up, however, did anyone check the driveshafts and u-joints? Ford did have some problems with a dry slip joint on the drive shafts. Steering damper is usually placed on the tie rod drag link and frame. As questioned if it is not doing it's job, wobble effect can develop.
Also as asked previously, does it do it in both 2 and 4 wheel drive? RPM at which it starts is important, always at the same RPM and/or speed ?

 

thank you for all the replys, I took it to a garge to align the front end and I found the problems, right inter tie rod that goes to gear box, right outer tie rod end and the 2 lower ball joints and the stabilizer steering shocks which I have 3 of are very weak, so once I fix all of that ill go back for an alignment and hope that's it...thanks again.

 

Ok, I fixed all of that and the vibration/bouncing is still there, ive put in new u joints in drive shaft and hanger bearing, and still I have the problem, I put it on jack stands removed tires both sides on rear and it is still there, now the driver side rear hub is very hot to the touch, but it makes no noise, could I have bad wheel bearings making it hot and could this be my problem all along? also there is a slight wobble on the rotor. am I on the right track? any ideas will be grateful. Thank You.