This Preliminary Information communication provides information to the technician about vehicles that have a Shudder, bounce, bucking from the rear of the truck while braking when towing a gooseneck or fifth wheel trailer. Technician will need to measure the actual truck and trailer weights, with the trailer loaded to the point that exhibits the condition. If any weight parameter is exceeded such as the Front Gross Axle Weight Rating, Rear Gross Axle Weight Rating, Gross Vehicle Weight Rating, or Gross Combined Weight Rating the load must be reduced before investigating further. If evaluation of the trailer?s brakes indicates trailer brake capability is adequate, adjust brake controller per the Trailer Gain Adjustment Procedure described in the Driving and Operating section of the Owner?s Manual and evaluate truck and trailer combination for braking shudder.
