Sorry to leave you hanging in the lurch like that, John, but I had hoped a Chev afficianado might have stepped in here while I was searching for my MB-C1.
The following is an excerpt from the Chev Maint manual. As far as I know, the C15 is the
only CMP, MCP or even WW2 2WD to have a traction enhanced differential fitted as standard. The Manual does provide a description and diagram of the unit, but it is not detailed enough to ID the mechanism. While not a Locking Diff as such, it appears to be a type of LSD, but of which type I don't know. Early LSDs were produced by Eaton as Posi-Locks, and Gov-Locks for smaller applications, but the CMP diff is in a sort of in-between zone between light-duty car diffs and heavy-duty truck/earthmoving diffs, and I don't know what applications were provided for in the early LSDs. It would have to rate as one of the earliest production installations of an LSD in a road-oriented vehicle.
