Quality: What buying by price gets
Here we have two samples of Diesel Motor Oil produced by YPFB, the Bolivian government plant. When it was owned by Petrobras they registered and made products to API standards, although they were still Group I base oils.
This first sample is their current best product: YPFB Multigrado Plus. It is new oil, taken straight from the drum. It has a CF-4 on the label, even though that is an obsolete category. You can see it barely meets the viscosity requirements of a 15W-40 and is very low in additives.
This sheet shows the results after 645 hours in a CAT 3516 stationary generator. The injectors have allowed diesel into the cylinders, lowering the viscosity to 10.8 cSt. Between the lack of boundary additives, low TBN, and the low viscosity, it has very high wear.
Here is a similar motor operating with a decent oil for 60% more time and half the wear.
