API Base oil classification

I would say GP I. The sulfur content is above .03%.

Group I base stocks contain less than 90 percent saturates and/or greater than 0.03 percent sulfur and have viscosity index greater than or equal to 80 and less than 120.

Group II base stocks contain greater than or equal to 90 percent saturates and less than or equal to 0.03 percent sulfur and have viscosity index greater than or equal to 80 and less than 120.

Group III base stocks contain greater than or equal to 90 percent saturates and less than or equal to 0.03 percent sulfur and have viscosity index greater than or equal to 120.

Group IV base stocks are polyalphaolefins (PAO).

Group V base stocks include all other base stocks not included in groups I, II, III or IV.

Thanks Michael. I had overlooked the "and/or" clause for the Group I oils only.

Is the product in question an unadditized base oil? Excess sulfur could be coming from any number of load-carrying additives. VI could be impacted by the use of PIB. A Grp I appears very likely, but in the absense of a tearapart analysis, I'd reserve judgement.

Best indication in finding out to which of the API grouping your oil belongs to is to run Aniline Point test ASTM D 611.

your suitabel lubricant is on clasification of din 51517 vdl