Hello from Afghanistan,(DEployed) I have 04 GMC,1/2 ton,2 wd,4-door,5.3. The problem I am having is I have a viberation between 85 to 92 mph and then it stops doing it the faster I go or I slow down. It has done this afterI installed the programmer to go faster...I took it to two different dealers with A IDK look.... I am fixing this problem when I return home, so doing my homework now...any suggestions ? Thanxs SKI

 

dont drive above 85mph, that is faster than the speed limit everywhere in the US

 

Funny guy....Still it should not do that!!!! And I like to drive fast...

 

make sure everything is balanced correctly, driveshaft, tires, etc. also check u-joints. does it vibrate in the front or back?

 

crew cab with a 1 piece driveshaft. it is too long. the only way to fix it is to convert to a 2-piece. they are pretty famous for flying from under the truck at speeds over 100.

 

Ouch, flying out at over 100....

 

Have you converted one? or has anyone done this...if so which truck did the 2 piece D/S come from..

 

The vibe, is in the rear...

 

if you are stock height then you can get one from a 2wd extended cab truck. all you will need to do is make a support for the center bearing.