After installing my TF 3" lift and rear upper control arms, I adjusted my pinion angle to align the pinion with the driveshaft following this post. The TF directions didn't provide any guidance for their adjustment, only a starting point. Of course my passenger side spring is rubbing on the track bar. I ordered Full Traction wedges to correct the misalignment of the spring.

After reading several post on here I now wonder if I aligned it right. Should I align the pinion to the shaft or match the angle of the shaft at the transmission? What angle will offer the greatest life of the shaft?

Thank you.

 

I believe your pinion should be set at the same angle as the t case flange with a stock shaft. check out the tom woods site- it gives you a diagram and a lot of other helpful info.

before I got a CV driveshaft, I had the stock shaft with the pinion tilted up a bit to lessen the angle on the rzeppa joint since it was pinched. I drove/wheeled like this for quite a while and had no problems- just a little vibration at high speed. If the joint is getting too pinched, I'd say to get a CV shaft and then you can do it right.

 

I read the Tom Wood info. He is describing U-joint shafts. He explains why the normal 2-joint shaft has to have matching angles at each end to eliminate vibrations caused by each joint moving through different ellipses. The double cardan joints eliminate the imbalance from the forward joint, so the pinion is brought into line in order to prevent the rear joint from rotating on an ellipse and vibrating. Pretty informative stuff I never gave any thought.

Too late for me to run out and look, but doesn't the stock rear drive shaft have a CV joint on each end? If so, then splitting the difference in the angle at each end would make sense, allowing me to lower the pinon back down and get my spring away from the track bar a bit. I believe then the limiting factor is binding with that pesky rubber seal on the stock joints.

I'll wait for more gurus to offer advice before making any changes.

Thank you.

 

I called the very nice folks at Teraflex. The guidance is to adjust the pinion angle to ensure the rear springs clear the track bar by the width of a pencil. if the joint is rubbing then relocate the spring perch. With an aftermarket shaft the pinion should be aligned as close as possible to the drive shaft.

There isn't much to the spring perch, so the best answer may be to relocate them vice replacing them with adjustable perches.

The gentleman at Teraflex was very nice and took the time to discuss their drive shafts (made in Utah with Spicer joints), aftermarket shaft maintenance and maintenance drivers, recommended control arm lengths, caster angle, etc.