Break in and ZDTP/ZDDP


Elizabethtown, Pa
There is an article in July 03 Lubrication Engineering (STLE) which indicates that ZDTP is highly effective in assisting the break-in process. That begs the question-might not Amsoil with its higher Zinc content be a superior break-in oil?? And now that Zn levels are less than 1000 ppm are we hurting ourselves during the break-in period. My guess is not, but who knows. [I dont know] Also is there a difference between ZDDP and ZDTP [Confused] I know Mobil 1 calls their Zn/Phos ZDTP . The article was to advanced for me- Hopefully Molakule has seen the article and can translate it [Frown]


Staff member
Iowegia - USA
Al, I am expecting the LE mag tomorrow, so I haven't seen the paper as yet. However, ZDDP, or ZDP, or ZnDTP, or ZDTP is the common name for the above and is chemically Zinc-Dialkyl-Dithio-Phosphate, an anti-oxidant and anti-wear agent. New zinc organometallic additives have appeared on the scene that have reduced phosphorus content, such as Zinc-diamyl-dithio-carbamates, or ZDTC, similar in structure to Moly DTC. ZDTC's are also metal deactivators, copper corrosion inhibitors, and anti-wear agents. I will attempt to respond as soon as possible.
Fairfield County, CT
Zinc, it's not just for fighting colds anymore! Based on the UOAs here, Toyota and Honda seem to prefer lots of moly during break-in. For North America in non-M engines, BMW uses the same oil for break-in as their service fill: Castrol TXT Softec 5W-30. For both break-in and service fill, SAAB's been using semi-syn 5W-30 and fully-syn 0W-30 with diesel-oil level of additives (more zinc and phosphorus), despite selling only gasoline-powered cars here in the U.S. Jason