The Stovebolt Site Forums The Shop Area Driveline SM420 mating To Torque Tube

I believe the crash box 4 speed U joint is also different
Need clarification ?

The four speed transmission front yoke for 1/2 ton torque tube,
is different from the 3/4 ton four speed transmission front yoke.

48-54 4 speed Front Yoke 1/2 ton Part # 3686323 (closed driveline torque tube)
48-53 4 speed Front Yoke 3/4 ton Part # 3686324 (I believe the 3/4 ton Front Yoke is enclosed, but the rear half of the drive shaft is open)
Technically both the 1/2 ton to & 3/4 ton u-joint assemblies are enclosed but different. The 1954 3/4 ton drive shaft is all open.
Source Grp # 5.555

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