Yes, diesels are low RPM motors. They also dirty up the oil quicker with soot. I have heard that about the anti foaming. Diesel oils were a quick fix when they started removing zinc from motor oil. The additive and detergent package is different. ZDDP and detergents are antagonistic in engine oils. Today, there are engine oils designed for our older flat tappet engines. They cost more. Diesel oils are cheaper. That is what it comes down to for some. Penny wise and pound foolish IMHO.
You know you may get a thousand different opinions, and most will be good advise, so take it for what it's worth. With my street engines and 800+ HP race engines I've used (or would have used) the following................ Oil............Joe Gibbs or Brad Penn for me. I've used Brad Penn for many years now and have had great success with it. Filters.........Wix, Napa(Wix), Car Quest(Wix), K&N, Purolater, System 1, just to name the ones I'd personally use. My preference is generally Wix.
I used Rottella T until I did some research. While the zinc and phosphorus numbers are adequate in diesel oil in general, it also contains a much higher level of detergent than oil designed for gasoline engines. Detergent counteracts the effectiveness of the anti-wear additives of the oil (Zinc or ZDDP). This is why Diesel oils are not recommended for gasoline burning engines.
I use Valvoline 10W40 conventional oil with ZDDP Plus and Wix oil filters. Easy to get and not too bad on the wallet. Changed every Spring (~1500 miles). When I pulled the rocker and valley covers all looked very good. Engine has never been rebuilt and has 108K miles. If I didn't run her year round I'd go with Valvoline 20W50 VR1...no need to add ZDDP Plus with that.
that is what i have here for the next oil change: http://www.amsoil.com/shop/by-produ...remium-protection-10w-40-synthetic-motor-oil/ i found the "flat tappets" on the label and take it, but not really sure if it was a good choice
