O`reilly has STP on sale for $2 and it contains ZDDP.

A link     http://www.lnengineering.com/oil.html

This came from a Porsch owner so it must be true, right? Pete

If you use 10/40, 20/50 or 15/40 (diesel) oil you don't need the STP if its not a new engine break in.



But yes, STP does have ZDDP in it, the one for small engines has the most so I am told (I think red bottle).

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Lucas now has a zddp additive in their line of products. Mostly for just break in, but I'd use it for flat tappet engines anyways just to help save the cam, and or the lifters. I've always used Delo 15/40 Multigrade anyways. I was told the bulk stuff may still have zddp in it anyways.

A lot of oil used to have zddp but it was taken out so IF IT DOSEN`T SAY ZDDP on the label THEN THERE IS NONE in it. Things change. Thats what happens.

That link to the Porsche forum article dates back to 2009. I bought some STP last week at Autozone. The new bottle is smaller now by an ounce or two I think and it doesn't say anything about ZDDP in the listed contents. I am wary of the diesel oils due to the very high detergent levels.

57 Black Tbird 312/auto

I think this statement is WRONG. It may be reduced, but not completely taken out. There is sufficient ZDDP in any oil that has a 40 weight or higher rating for ordinary running. I would ad an additive if breaking in a new cam. Even Ted Eaton says there is enough ZDDP in 40 wt or over oil.



While I didn't remember specifically looking for it, I doubt that the contents mentioned ZDDP. In fact, I am not sure contents are required listing for motor oil. I don't remember seeing it on either the old or new Rotella T, both of which have lots of ZDDP

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

OK. By on the label I mean API SERVICES SM/SL

                                       ILSAC, GF-4

                                       And all preceedingAPI & ILSAC

                                        Gasoline catagories

You will have to do your own homework, I got other stuff to do. Pete

If the label says for gasoline engines only, stay away from it because the zddp has been cut back too much for flat tappit cams and the label ( for gasoline engines ) is usually on oils with 30w or less.

-Gary Burnette-