ZDDP history

[morgan4]

Greetings... This may have been discussed before but I couldn't find a thread about it. How long has ZDDP been used in motor oil. Is there a patent date covering its use? I suspect it is about mid 70's. TJ

 

[JAG]

I won't cheat and will go off my memory: 1940s? A Google search should tell you. I'll check back here later and see how good my memory is.

 

[wileyE]

Since hypoid style rear ends replaced chain drives in trucks. Can't remember the year either. I believe it started in gear oil 1st.

 

[bruce381]

from memory I'd say about 1930 or so.
bruce

 

[Blue99]

When did ZDDP start showing up in API service grade oils?

SA - Straight mineral oil.

SB - Minimal wear protection requirements

SC - 1964 Model year requirements

BTW - This is a very good topic, of general historic interest to everyone!