I am having a bad vibration when taking off. It gets stronger when I am pulling a trailer. The vibration is worse in reverse than any other gear. At times the truck shakes so violenty that I have to stop and start again. I have been to the dealer twice about this, they pressure-tested the clutch and said it was like new. They are currently looking for answers. The truck has 27. 000 miles on it, and has been doing this since it was new. Does anyone else have this same problem? I would greatly appreciate any help. 2003 quad cab, 4x4, short bed, manual transmission