Originally Posted by user151
If the trans down angle and the pinion up angle are set equal, that is good... then raising (or jacking up) the vehicle will increase those angles, but they will still remain the same and opposite.
So the rule remains true: the trans down angle and the pinion up angle should be the same.
Of course, too large an angle will result in short U-joint life.
Actually in almost all setups, when you raise the whole car the trans output angle does not change. The rear pinion will definetely change as your 4 link setup will either pull the axle closer or away to the output shaft of the trans. This really is not that difficult to understand. I'm surprised there is so much false info floating around.
To make things more difficult, take into consideration the rear axle lateral movement from a panhard bar as you raise and lower a car. Mind blowing stuff isn't it....? (sarcasm)