jacked up truck checked both tires absolutely no play there, not he wheel bearings. I rotated the tire when it was jacked up and noticed some play in the driveline when rotating forward to reverse. seems to be comming from the differential. Also notice the drive shaft was rotating slightly oblong from the carrier bearring to the rear dif. but there is no play in the u-joint. This is causing a slight vibration at higher speeds. Could this be caused by impropper load on the pinion bearing/ shaft? or do i need to replace some parts in the rear?

 

It could be anything from improper preload on the pinion bearing to a bad pinion bearing. Also check the u-joints, when they go bad they can cause vibrations

 

I think you need more fiber.

 

more fiber?

 

It helps with irregularity in the rear end.

 

ha ha! Ill give that a try, thanks.