DriveshaftsV2

[Vineboy]

Just a quickie.... Ive just had some drivetrain work done and have a question re driveshaft orientation. Do the yokes on the rear driveshaft and the jackshaft have to line up or seat at 90 degress to each other? I'm getting really bad vibrations.
Cheers

[mud4b]

yes they do have to line up with each other.

not at 90degrees.

[JrZook]

There should be indents on both parts of the driveshaft to line line it up.

[PJ.zook]

It is vital that they exactly line up, otherwise vibrations and damage will occur.
If you actually watch a driveshaft with uni's both ends turn, you will notice it doesnt turn smoothly, it actually speeds up and slows down twice per revolution, doesnt matter what speed its going.
When the uni's are lined up, they cancel this speeding up and slowign down motion. The first uni creates the movement, and the 2nd uni converts it back into smooth rotating motion.

[Vineboy]

The rear driveshaft was out by 30-40 degress so I got it back in line. Made a huge difference but still vibrating. I suspect it's now the jackshaft becuase when I put the transfer case in neutral and select first in the gearbox at about idle speed and climb under the car, I can see the lackshaft turning but it wobbles from side to side about 5mm. This has just had work on it to mate the 1.3 5 speed with the 1ltr tranfer case. I may have to take out the jackshaft and get it balanced properly.