727 - Driveshaft Jammed All The Way In

There are at least 3 different yoke lengths avail.
That looks awfully long, but hard to guess .
I have been collecting 904 slip yokes, I have a long one and the rest are shorter. The long one slips into the transmission and goes all the way in with no interference. I read a TSB??? that the yokes all had longer ends till it was discovered it caused a driveline vibration so they all got shortened. The long end does not have any splines in it and it is a smaller OD than the seal area. If the long one was cut off at the step in the OD it would be exactly the same length as the short one

Left, 904 of unknown origin (I suspect aftermarket)
Long, bought as 904 yoke
rusted one, 904
On the right OEM from the car when new

all measure the same OD on the seal area

all have the same splines

all have the same U-Joint dimensions

I just show this to say that the yokes might be able to be significantly longer without any interior transmission issues.

(not commenting on the driveshaft being too long)

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