A little background here. I'm an American expat living in Kyrgyzstan. I own and run a car rental company here. We have been using Total full synthetic 5/30 and 5/40 for various vehicles (Ford Ranger, UAZ Patriot, etc). Those cars serviced with Total are frequently developing engine problems before 100,000 km including cylinder damage, main bearings, and similar faults that can be attributed to oil quality. We are using OE filters (except UAZ, we use better than OE) and doing oil changes with full synthetic every 7500 km. Our Renault Dusters were serviced at a different shop and used a couple different oils (shop didn't always specify) including Elf (owned by Total) from a different distributor. We have had 0 instances of major engine problems with the Renaults. My conclusion is that the Russian Total Oil supply has a quality problem, or it's being substituted with junk oil somewhere in the supply chain. This has led us to open our own shop and we're looking to purchase oil. I can get Liqui Moly, but for fleet use it's expensive and ordering a barrel takes several months. Naturally I want to stay away from Total products. Castrol is distributed by the same company as Total, making it suspect. That leaves us with Addinol, Kixx, and a limited supply of Valvoline. I'm leaning toward Kixx as the distributor brings it directly from Korea and it is economically priced. Thoughts? Experience? Research? The internet isn't much help in English or in Russian.