> Drilling and tapping may not be enough. There may not be enough metal
> in the housing to allow for a good bite by the drain plug. You may need
> to weld on a bung.
As someone already noted, there is a place provided in the casting for the drain
plug. It's thick enough.
Simplest is probably to copy the factory's practice (on the earlier diffs) of
using 1/4" NPT threads, which take a 7/16" tap drill. Note that, since the
threads are tapered, you don't run the tap all the way through. I like to stop
early and test the plug for fit.
Randall
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