Welcome to the Stovebolt Page. Glad to have you. Tell us more about your project. Is the 4-speed a truck trans like we are guessing? Does it have the little lever/rod to put it in reverse? If so then it's a non-synchro pre-48. What's it out of? Nifty50 is right, if it's a SM420 and has a torque tube ball/socket on the end then it's from a 1/2 ton or 3/4 ton. Bigger trucks at least from 48 had an open yoke. Good luck. smile


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