Vibration ?

[fabman_52]

I have a 1990 Ranger 2.3 5 speed, had a vibration in the drvieline. felt like U-joints so I replaced them, no change. Had a broken motor mount, replaced that, no change. Trans mount and other motor mount are fine. What else am I looking for? Just put new tires on with hi speed balance. It's pretty bad between 45/65 mph. I drive 60 mi. for work everyday. So I need help asap.
Thanks Ahead.

 

[metalmacguyver]

Start by verfiying exactly where it is. Jack the truck up, put the axle on jack stands, REMOVE THE TIRES!!! and put it in gear and see if you still have the vibration.

If you do, take a look underneath, chances are that if you look close, you can see the vibration.

Try seeing if the drive shaft is straight. Put a dial indicator on it and rotate it by hand. It should be less than 15 thousanths.

 

[pimtool]

If the weights came off when you put the U joints in that can cause a vibration. Also dents in the drive shaft will shake things up.

 

[Mechanickid]

Its a small thing but, did you mark where the u joints were originally seated? Drive shafts are balanced as a unit from the factory and can vibrate if not replaced in the same flanges.