Anyone else seen this? looks like some decent oil for the earlier trucks. I am thinking about giving it a try. Here is some info http://www.lucasoil.com/images/medialibrary/30_15W_40_Magnum.pdf
According to the spec sheet, this oil doesn't have a very high "VISCOSITY INDEX" meaning it will vary in viscosity over the operating temperature range more than an oil with a higher VI INDEX. The best oils with the highest VI will remain stable and not vary much in viscosity over the temperature range. This allows for consistent engine performance within the normal working conditions.
131 isn't very high? Anything over 110 is considered VERY high. The other nice thing is it is CI formula.
Looking at Amsoil site the better Amsoil 15W-40 has a VI of 146, a little better but not drastic, but it only has a TBN of 10. 4. I don't want to get onto a AMSOIL fight, it is good oil, but it is not the only oil. You have to admit, as far as non synthetic oils go, it's not bad, and better than almost all of the CJ formulas out there.
Anyone ever ran Schaefer Oil?, Probably spelled it wrong, was wondering , i just changed my car oil and had them put this in, it's suppose to be full synthetic, It was a free oil change and they were raving about it, My son runs a shop and he says it's really good, anyway i'll try it if i don't like it i'll get rid of it, they also give you a sample bottle and check it for free, Monte