Originally Posted by Benzadmiral

Trueog,

Right now I use a 70/30 mix of Chevron Delo 15W-40 and Havoline 5W-30 in my '97 C230, which I believe is the same engine as yours. Havoline and Chevron are the same company, and all good modern oils are pretty much compatible anyway, so mixing is not a worry. I do it to thin out the 15W-40 a little to eke out as much gas mileage as I can. (It probably makes almost no difference, but it's fun to see what I can achieve.)

My climate in Da Swamp is nastily hot for 8 months of the year, and less hot to once-in-a-while cold for the remainder, so I don't have to worry about my oil being too thick at startup.

The important thing to remember about 15W-40 is that it's used all over the world as a "universal" oil, in heat and cold, in diesels and in gas engines (because it's rated for both, "S" as well as "C"). The Chevron Delo is considered a super-dino oil by many, and a bargain next to the synthetics if you don't need synthetic. Dino oils these days are so good that if you don't do extended drains or have other severe service issues (like a turbocharged engine), synthetic is a waste of money.

As far as price, there is Havoline, being sold in the States at about $2.00 USD a quart, and Conoco/Phillips's TropArtic synthetic blend, going at Evil_Marts for about $1.68. But neither offers a 15W-40, as far as I know.

All the major oil companies make really good oils. You don't have to $pend a lot to get good oil.
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