Quote: I run Shell 15w-40 Rotella diesel oil. You need the Zinc for your cam. Most passenger car oil had the zinc reduced to a potentially dangerous level.
This is what i use in everything.
New Rotella CJ grade oil (has flower symbol on the bottle) has reduced Zn & P from previous levels. This is to accomodate the 2007 and up low emission diesel engines with particulate filters. Also, there is more to it than Zinc. Diesel oils have higher than normal levels of zinc, because they tend to have higher levels of detergency. Studies have shown that the high detergency wants to clean off the anti-wear coating laid down by the Zinc package. Thus they added more zinc to help that. I have been told to avoid the new CJ diesel oils with the reduced Zinc, even if they say its backwards compatible.
An affordable buy for an off the shelf oil seems to be the Valvoline VR-1 20W-50 which has a detergent package suitable for a street engine. About $4 per quart at the store. Regular Valvoline Racing oil in the black bottle is non detergent which shortens the drain interval.
Brad Penn everyone raves about, but you buy it thru a distributor. Here it's about $6 a quart including shipping.
A couple weeks ago at our local Fleet Farm, I bought some of their house 10W-40 oil which is Citgo packaged and is the older API SL grade (SL has more Zn & P than the new SM oils).
