Quote:

The u joints don't know the difference in angles from left to right and from up and down, the rear U joint and tranny yokes will know when overly misaligned

stressed I would never have a upside down V angle (The pinion pointed up and the drivesahft pointed down) between the pinion angle and driveshaft angles when sitting still, NEVER



Since you are correct in stating the u-joint doesn't know left/right/up/down - here's a sloppy chart to show some scenarios. All are viewed from side and referenced to ground.

Top one is engine level, u-joint 4*^,(driveshaft 4* dn) u-joint 4*v, pinion level.
Next is engine 2* dn, u-joints 2*^,(driveshaft 4*dn) u-joint 2*v, pinion 2*up.
Next is engine level, u-joints 2*v, (driveshaft 4* up) u-joint 2*^, pinion level.
Bottom is engine 2* dn, u-joints 4*v, (driveshaft 4* up) u-joint 4*^, pinion 2*up.

All scenarios leave the engine/trans and the pinion centerline parallel . Top 2 are typical street car - bottom 2 are more chassis/big tire oriented.

And again - these are UNDER LOAD scenarios - how much more the pinion needs to start out pointed down from these figures vary by suspension type - could be anywhere from 1-7*.

8357942-Angles.jpg (81 downloads)
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