Drive line angles

finally measured  some angles from the drive line.

I removed the drive shaft from the rear:

- pinion yoke  1.6 degr positive

- transmission tail end  1.8 positive

-crankshaft  end at the front of the engine  1.6 positive

There may be some  accuracy issues but  in general  I think  this gives an overall view to the situation

I have learned that  the angles should be  slightly negative rather than positive...

I think that I will put  2 degr  wedges on the leaf springs to get  a bit  nose down  pinion.

What do you say ?

Can you make a little drawing?

Saying that an angle is positive or negative requires some sort of reference. It might be better to describe if the flange /shaft is pointing down towards the ground or up at the sky.

Hi

I mean upwards when saying "positive" - sorry for the inaccuracy !

This may help. http://www.quickperformance.com/Pinion-Angle-Measurement_ep_45.html

The transmission angle should be downward (negative). The pinion angle should be upward (positive). The two numbers should be 1 degree, numerically, of each other. Think of them as canceling out to make 0. You also want the two numbers to be less than 5. I have found the best place to take the transmission drive angle is at the rear of the transmission housing, next to the seal.. For the pinion angle, get a machined surface horizontal, then take your measurement on top or bottom, making sure you are using the machined surface. If the transmission is off, you use a spacer to achieve the desired angle. If the pinion is off, you use a pinion angle shim (metal wedge) to set it. Pinion angle shims can be ordered in degrees. I hope this makes sense and it helps.

To prevent vibrations it is important to have the angles on the front and rear u-joints within 1° of each other (but at the opposite angle) so the angular rotation speeds cancel each other. You also want to make sure there is some angle so the the needle bearings move around some for even wear on the pinions, cups, and needles. Here are some good instructions:

https://www.drivelinesnw.com/part-trouble-shooting/vibration-analysis/angle-analysis/measuring-and-correcting-angle-problems/