Setting Pinion Angle

ratrodderlc said:

I'd like to jump in for a moment and relate what I've been through in the last couple of years with regards to pinion angle problems. The shop I trusted to install a set of ladder bars on an 85 silverado for strrip and show ended up with an angle of plus 8 degrees! I knew very little at the time but through a painful learning curve I solved it. My truck experienced severe vibration between 3200 and 4000 rpm. Changing the angle to minus 1 degree solved the vibration problem. As long as the angle is negative, at rest , you will be good to go!

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also a good trick learned this from my dad with our drag truck we had years ago with chevy -2 degrees works really good and -1 degrees works also but with -2 when you hammer on it it will go to straight in line from tranny to diff no matter what also helps in torque and traction

angle

i would check the angles with all 4 wheels on the ground.that way your suspension is loaded. with the wheels off the ground things are different.
if the rear end yoke is angles down too much you can get shims to change the angle. they look like front end shims but thicker. i worked for company
that had a lot of big-truck 4wheels drives that were used off road & driven
on interstates also. if the angles are too severe or too straight it will normally show up quick. you will get a seal beat out & them loose a u-joint,
driveshaft,transmission pan or even worse. we used shims to correct rear pinion angle. on rare occasion we would have to lower the tranfer case to take some angle out.

shakey56 said:

He sets his at the same as the trans angle but opposite. Trans -8, diff +8. Whatever trans angle, diff is the same but opposite.

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+1 This is the most ideal way to set it up if at all possible. Always remember "equal but opposite angles". This is true up and down and side to side. doesn't matter where your car sits it is the angle of the front joint in relation to the rear joint.

On the slip yoke the standard amount of clearance (at least on a GM trans) is 3/4"-1" out at ride height. This is how we measure for all of our shafts. Set the car to ride height, push the yoke all the way in, then pull it out 3/4"-1" and then measure for the shaft length. Just my $.02