Another interesting fact. When an
oil qualifies under, or gets an API C license(diesel), and then subsequently gets an SL license(gasoline), the phos limit of .10% for the SL license is waived. I think there is also a viscosity limit on the phos requirement in SL oils, but I don't have that answer as yet.
David:
The Delvac 1
oil now has the CI license as of September 1, and probably has an SL license also, but I haven't seen it. It is more expensive than Mobil 1, but $5.00/qt sounds high, but I don't remember what I paid for it last time. Rotella T is a very good
oil and will give you excellent service. The .10% max phos level in the S oils begain with the SJ license and is carried thru to the current SL formulation. However, I believe that the phos limit only applies to oils with the "Starburst" certification mark and that is associated with 0W-XX, 5W-XX, and 10W-XX cross graded oils where the XX does not exceed an SAE 30 viscosity.
Jerry