BLS, Thanks for the reply. I will look at it todayBLS2DWL said:I have run into this problem with trucks that have front abs. When we are diagnosing drivetrain noises/vibrations we will jack the rear of the truck up on jackstands and run the vehicle @ high speeds sitting still. what happens is that the speedo and the abs sensors on the front wheels dont agree. One says 60 mph and the other says the truck is sitting still. Check your abs connections or sensors to make sure they are not contaminated.