Thanks for the additional info, Greg and Rod. I just confirmed the 61-7/8" length from front flange of torque tube to differential housing flange. So it appears this is from a 128" wheelbase Buick Master Six. I took the rim off the felloe on one side (the nuts came off the studs easily and the rim clamps slid off). The inboard flange of the fellow measures 23" OD, and the ID of the rim is ~22-1/2" inches. So I think this confirms with Leif's suggestion of a 23" wheel, which is evidently a 1924. The inside of the farroe had this marking of 32 over a "/ 2". I do not know what that means.
I took off the differential cover and drained the lube. Everything appeared to be wet with lube, and I saw no rust or other obvious damage. The ring and pinion teeth look good, although I did not wash off the old lube off to inspect in detail. The ring gear is about 12-1/2" in diameter, with 52 teeth. The pinion has 11 teeth, for a 4.73 ratio. The differential has 4 pinions, and the safety wire retaining the differential nuts is intact. Everything spins freely.
Whomever winds up with this will have to excuse me for the RTV I used to repair the old paper gasket and button it back up. I wanted to make sure it sealed, and I filled it up again with some 80W-90 gear oil I had sitting around. That should be good enough to keep everything inside wet with gear oil. Whomever does the restoration will want to go through everything inside anyway, so this is just for safe storage.
Thanks again to everyone for the help in identifying this. It looks to be a rear axle for a 1924 Buick Master Six with a 128" wheelbase. I will post this for sale in the Buick section. I paid $270 for the axle, thinking I would have a couple antique wood spoke wheels to hang up in the garage and the rest would be scrap. But this axle is too complete to do that, and I would rather see it wind up in someone's restoration. I honestly do not care if I break even or lose a bit on this purchase. It has been a fun learning experience, and I may have met a new friend or two in the process. I am happy to pay a favor forward, and others have done the same for me in this hobby.
Cheers,
- Brad Zigler