This end has been buried for several years. Pulled and cleaned today and confirmed my suspicions about the axle having been run without lube. I have already replaced the bearings. [img]https://imgur.com/2fUaalI[/img]
Last edited by Grigg; 05/07/201912:20 PM. Reason: Title
1953 Chevrolet 3100 261 cu inch, sm420, 3.55 rear, torque tube still,omaha orange, still 6 volt, RPO green glass, side carrier spare, all done In the DITY Gallery Video of the 261 running
1964 GMC 1000 305 Big Block V6, sm420, the next cab off restoration
Possibly... If the bearings were smoking hot the hub would have to be very hot enough to transfer heat to the axle flange. (the wheel bolted to the hub would also be really hot) If that happened I'd suspect the entire axle flange in contact with the hub would/should see the same temp and color change That is not what's shown with the outside portion of the axle flange being cool, no color. The color pattern indicates the axle shaft was the hot part and the heat didn't quite travel out to the outside of the flange.
I'd guess the colors on the axle shown are a result of the manufacturing process, tempering, and not an indication of previous severe bearing trouble.
That looks kind of like induction hardening done on current production axles and bearing hubs. But I don't believe that process was used back in the day. My guess would be that the bearing surface got pretty dang hot. But I would guess that the axle surface where the bearing runs would be pretty torn up if it ran like that for very long. That color looks to be hot enough to draw the temper out of the axle. If it were mine I would get a hardness check at various spots (close to the bearing surface, for sure). If it's softened, even if not already scarred up, it isn't going to last long.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
Isn't that color a result of the flange being welded onto the axle during the manufacturing process? I seriously doubt that GM turned down millions of 4" diameter solid billets to make their axle shafts. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
They are forged, I expect they first upset the end (make it larger and or with more metal) then finish forge the flange to shape, if not done all at one wack. The color is on top of the finished machined part, so the heat was applied after machining. I see no evidence of spin welding a flange to a shaft, and even if so it's likely the flange was finish machined after.
I still suspect the heat/color is a result of heat treating and or tempering the shaft at the very end of the whole manufacturing process.
