I have always been told that the fixed yokes (those attached to the driveshaft) should be in the same plane whether is be on a vehicle or PTO shaft. I am told that this prevent the two ends of the shaft from trying to turn at different speeds which, I guess, is why CV joints were invented.
I am no engineer, but have been told this by farmers and mechanics all my life.
I checked my Kubota Workshop Manual and it does not "say" anything about the alignment of the yokes. The exploded view of the front drive shaft however, shows them "in phase".
I had my B2910 back for warrenty replacement of the plastic front driveshaft cover.
Was talking to the mechanic and he told me that when you take the front driveshaft off, you mark it first, and put it back the same way. Otherwise, according to him, it will fail prematurely.
Don't know myself, but that is what someone that should know said.
<font color=blue>… should the yokes on the front driveshaft (4WD from the tranny to front diff) be in phase?...</font color=blue>
If I understand you correctly… on a drive shaft/pto shaft… both the front and rear u-joints or yoke assemblies should be aligned/in-phase/in-sync with each other to keep the “shaft assembly” balanced… (obviously the shaft by itself should have been balanced by the OEM)…
When you change a u-joint or entire yoke assembly at one end or the other… the replacement should be the same as the original (in-phase)…
When the shaft is out-of-phase... this usually causes an "unbalanced" situation and vibration starts... very popular with inexperienced implement hookups... (split PTO driveshaft not assembled properly)...
<font color=blue>(split PTO driveshaft not assembled properly)... </font color=blue>
This is why I am glad someone painted a white stripe on both ends of my mmm driveshaft. /w3tcompact/icons/smile.gif
All the kubota shafts I can think of have a "tabbed" spline and or roll pin to prevent you from making this mistake. The white paint just makes it easier to line up the "tab". Most Pto shafts (for rear mounted mowers, tillers etc.)are set up with a way to ensure proper alighnment as well. Thats why the slip shaft is rectangular or "goofy" shaped.