Thanks to everyone that has replied.
It appears that there are two and maybe three lubes suitable for the worm drive rear with yellow metal used in the 1926 to 1934 STuTZ cars.
1. Penrite T140.
2. Mobil SHC 634.
3. New Holland if L6 can confirm a part number.
Oldcartech: I enjoyed the article on Machinery Lubrication. Thank you. I spend my early years, many many years ago, in a hot strip mill where we rolls steel slabs into coils of thin steel. We had many large (10K HP) gear boxes. I was not involved in the maintenance of these gear boxes since I was in the electrical group but I know that a lot of time and thought went to the selection and constant analysis of the lubrication.