[Shop-talk] Oil grade selection

[Doug Braun]

The ZDPP articles I have read have said that modern
engines are not affected because they have roller
tappets instead of flat tappets.  But obviously not
all (or even most) modern engines have roller tappets.

Does anyone know what the articles really meant?

Doug

 
--- Steven Trovato <strovato at optonline.net> wrote:
  As for the reformulation, the latest
> crop of motor oils 
> have removed or greatly reduced a component called
> ZDDP.  There has 
> been much talk in classic car circles about this,
> and the possible 
> negative effect on "flat tappet" engines.  If you
> have such a car, I 
> suggest you look at one the many articles on the
> subject.