Waking up this old thread again, albeit with a solution rather than a question.
I recently did some work on a W460 for a friend who had swapped in an M113 (5.0 V8) mated to a 722.9 (7-speed auto), both off a donor 2005 S500. The W460 transfer case was retained, as were all the axles and shafts, except for the propshaft that goes between the transmission and transfer case:
What I found installed here was a sort of Frankenstein propshaft, with a cv-joint on one end and a U-joint on the other, with both ends welded onto imbalanced and poorly machined flanges to adapt them to the 3-bolt transmission output flange of the 722.9 (which is the same as that of the 722.6 [5-speed auto]) and the 8-bolt transfer case input flange. Take a guess as to what the problem was with this setup...
Having decided there was nothing we wanted to salvage from the existing propshaft, I decided to search for a solution. By reading through several forums, it was evident that the stock U-joint shaft on the W460 was problematic, and not easy to source either. Also note that the distance between the transmission output flange and transfer case input flange was 306mm.
After a bit of Googling, I came across the cv-joint style propshaft of the
G300TD W463 (P/N: A4634100502), which has an advertised length of
237mm (9.3"). These can be bought relatively cheap (approx. 130USD). This is what we decided to go with, so all that was left was to make the suitable flanges to adapt both ends to fit the application.
Once we received the shaft, I measured up the CV joint ends of the shaft, as well as the transfer case and transmission flanges and got to work modelling them in CAD:
That was followed by some 3D printed prototypes to verify that the fitment was all good:
Once the design was locked in, I did a quick FEA (finite element analysis):
Satisfied with the results, the drawings were sent to my trusty local machine shop:
And that’s pretty much it. A simple cv-joint solution to the W460 propshaft issue. If any of you think this could be useful for your application, or if you have any questions about this, let me know.