Originally Posted by smithlawncare2004
my truck have a bad vibration all there acclaration gets really really bad in over drive around 50 to 55 mph... ive checked the u joints ,carryer bearing,took the cover off rearend and spun it around it looks to be fine. put truck on jack stands and put it in gear and watched everything spin and mover cant find nothing !!! Anyone have any ideas ??? please help
This may be of some help
Vibration/Hop at 40-48 MPH, Trucks with Trailer Hitch:
Some 2005-07 F-Super Duty trucks with long wheel base (over 156") may exhibit what is described as a hop on smooth or coarse road surfaces. Although Ford conciders this to be characteristic of trucks with a GVW of over 8500 pouns, some drivers may be more sensitive to the condition. There is a damper kit (P/N 5C3Z-5D008-A) available to correct the hop under the described conditions. It will not correct shimmy, harsh ride or vibration after hitting bumps. TSB #07-5-11.
6.0 Moan/Droan Between 1500-2000 RPM:
Engineering has investigated this condition and found the cause to be engine firing pulses causing the turbo mounts to vibrate/resonate. For trucks built through 9-29-03 install a revised turbo pedestal, P/N 3C3Z-6N639-BA. Trucks built after 9-29-03, install a turbo bracket A-brace, P/N 5C3Z-6N639-BA. If the draon is still present after installing the brace on trucks built from 9-30-03 through 1-17-05, replace the turbo pedestal with 5C3Z-6N639-AA. Ensure the droan is not caused by a bound exhaust system. Inspect for any damaged or broken exhaust hangers. Check the turbo downpipe by loosening the pipe at the top and bottom, checking its alignment and retightening. If the droan is still present, check the part number embossed on the turbo pedestal just below the turbo compressor outlet to the intercooler. If the number IS NOT 1846207C1, replace the pedestal with the above part. After replacement, or if the number IS 1846207C1, loosen the turbo inlet pipes and EGR cooler flange and neutralize by installing the components in this order: snug the flange between the LH and RH inlet pipes; torque the EGR cooler clamp to 53 in/lbs; torque the pedestal bolts to 23 ft/lbs; torque the turbo inlet clamp to 9 ft/lbs: snug the inlet pipes to manifolds. Ensure all components are properly aligned. Torque the flange between the LH and RH inlet pipes to 20 ft/lbs and the inlet pipes to the manifolds to 20 ft/lbs. Broadcast Message 0992, SSM 17530, TSB #04-9-4 & 05-19-12.