when I swapped out of the zf6 to the 700 r4, I bought a yoke for the 700r4, my shop told me it was too long, and instead of shortening the drive shaft, I had no money for that.

we chopped the yoke, my input was the C beam held the "distance" and the drive shaft would never contact critical part within the trans. so we could be conservative and just take off a little as little as 1/4 inch.

the yoke ended up looking factory fresh with no signs of shortening.

is my theory correct that the c beam would prevent any inward movement from the driveshaft?

I am a little concerned, if it did make contact what damages would/could occur?

If its too short it will push the tailshaft in and possibly give you some damage, can also screw with the pinion. WHen you accelerate/decelerat/go over bumps the housing wants to move up or down some pulling the DS in or out a touch.

I do not know if the Cbeam could prevent this Im going by straight axle stuff.



If it is contacting they shouldnt have let the car out the door.



Do you hear any vibration/strange harmonic noises?
Any signs of aliens?

Yes, with the C-beam in place there should be no movement of the driveshaft relative to the trans, except for some miniscule amount from beam flex.

FWIW I believe the C beam also sets the driveshaft at a slight angle in order to keep the needle bearings in the ujoints moving.