Based on all the reports of people welding up broken housing from diff bolts coming loose/braking from the different sites I am convinced the housings are cast steel . Harry , you being the resident expert welder . Could you do a spark test on a couple of your housings to set the record straight once and for all . I relalise you will need to touch up the paint afterwards .
Based on what I beleave to be true . This is from a welding site .
How to weld cast steel
Learning how to weld cast steel is less of a challenge compared to cast iron. That’s because cast steel is carbon or alloy steel that has been melted and molded into a specific shape. However, even though cast steel has similar properties to rolled steel, some differences make it harder to weld.
Although you can weld cast steel using the MIG or TIG processes, many welding experts recommend stick welding with E7018 rods for low-carbon alloys and stainless-steel rods for hard-to-weld castings.
One of the issues with welding cast steel is avoiding distortion. Here are some suggestions to help with that:
Preheat the casting: Castings can have irregular shapes, with thinner areas heating more quickly. Concentrate the heat on thicker regions.
Tack weld frequently.
Set to the lowest amperage that will produce a strong enough weld.
Use the fastest traveling speed possible.
Use fewer passes.
Slow down the cooldown by wrapping it in welding blankets or burying it in sand.
A few more tips on how to weld cast steel successfully:
Clean the edges to be welded down to the bare metal.
Preheat cast steel if it has more than 0.40% carbon or it is low-alloy steel. Preheating to 250°F prevents hydrogen in the weld.
If you weld in a cold environment, preheat low-carbon castings to 75°F.
If you are repairing a crack, drill both ends (1/8″) and remove the crack by grinding or gouging.
