2008 F-350 Dually 4X4 King Ranch with under 12k miles, Hauling 29 foot fiver Canyon Trail RV. This is my first big truck. I have run into a problem with it and I'm at my end with it! This is the problem, with the RV hooked up in tow mode I can feel a strong forward and aft jerking between 35 MPH to 55 MPH. With tow mode off the jerking is ligher at the same speeds, above this speed everything is smooth. Without the fifth wheel hooked up at the same speed and tow mode off the jerking can be felt very lightly. The truck has been in the in several shops with and without the RV. I have gotten replies back from these these are, if it does not show up on the computer there is no problem!
sounds simular to an earlier vibration problem they had....
-------------------------------------------------------
-------------------------------------------------------
FORD:
2005-2007 F-Super Duty
ISSUE:
Some 2005-2007 F-Super Duty vehicles with a long wheelbase of 156", 158", or 172" (396, 401, or 437 cm) and equipped with a trailer hitch may exhibit a vehicle vertical vibration, often described as "hopping", on smooth or coarse road surfaces in the 42-48 MPH (68-77 Km/h) speed range. Although this behavior is considered normal for an over 8500 GVW truck, some customers may be sensitive to the concern.
ACTION:
To improve the 42-48 MPH (68-77 Km/h) vertical vibration, follow the instruction sheet included in the Damper Service Kit.
NOTE: THE INSTALLATION OF THIS DAMPER WILL NOT IMPROVE RIDE ON SEGMENTED CONCRETE HIGHWAYS, STEERING WHEEL VIBRATION/SHIMMY, OR GENERAL HARSH RIDE CONCERNS.
PART NUMBER PART NAME
5C3Z-5D008-A Damper Service Kit
WARRANTY STATUS:
Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
IMPORTANT: Warranty coverage limits/policies are not altered by a TSB. Warranty coverage limits are determined by the identified causal part.
OPERATION DESCRIPTION TIME
070511A 2005-2007 F-Super Duty With Trailer Hitch: Install The Damper Service Kit. 0.6 Hr.
DEALER CODING
BASIC PART NO. CONDITION CODE
5D008 42
----------------------------------------------------------
----------------------------------------------------------