I need to know what the axle housing is made of, cast iron or steel since I have to have the u backet re welded.
On local guy says they are made of steel and another says cast iron.
Its a 1970 if that matters.
So, is it steel or cast iron ?
Thanks

Steel

I VOTE for Cast Iron Center section with STEEL tubes pressed into either side to form the differential housing......Chuck/Seattle

The center is cast nodular iron, the same thing cast crankshafts are made of, and any welding that you do on it will change the heat treatment in it. You need a very experienced welder to work on it. The axle tubes are mild steel and can be easily welded.

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'69 RS/SS396 pro street
427/4spd/9"
Byars Performance
High Performance Drive Train Parts And Service
www.lubedealer.com/biggearhead (http://www.lubedealer.com/biggearhead)

So how does one weld the axle tubes to the housing, like some racers do? I am thinking of doing this myself.

In production, the tubes were pressed into the center section, then they were "puddle-welded" together, then the assembly was heat-treated (annealed) to relieve the welding stresses.

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JohnZ
CRG
'69 Z28 Fathom Green