Pre 55: Torque tube driveline. The driveshaft is enclosed in a tube fixed to the rear axle. As there is no rear u-joint, the axle is hinged to the springs. The spring perch has a pivot point, and the locator pin is forward of the axle.
55 + later: Open driveline. The driveshaft is exposed, and there is a u-joint at the rear. The axle is hard-bolted to the springs.
Having said that, I can't see why the 55's are more expensive. Do the 56-59 fit?
Current fleet (subject to change w/o notice) \'49 GMC 3/4-Ton , 60 Austin Healey Frog-eye Sprite (some assembly required), 2011 Dodge Avenger, 2015 Jeep Cherokee. No, they don't all run. My other ride is a (B737)no, (B767)no, A320.... Update... was Embraer E190, now Boeing B787. Knowledge is a wonderful thing, but ignorance means you don't know you can't do something.
| 
