If you need the speed, buy a custom racing shaft. Drive shaft RPM approaches engine RPM and that is waaaaay too much for a factory tube.
The shaft needs to be built perfectly straight and then balanced.
Look at your shaft (the one on the truck!) and you will likely see little square weights tacked onto it. It is balanced for common highway speeds, not high speeds.

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2006 4.0 5 spd auto 4x4 Super Cab
BF Goodrich Commercial Traction T/A's
Royal Purple Throughout
Alpine Head Unit with some Infinity Noisy Stuff
NW Oregon