For the same reason racing oil has elevated ZDDP, antiwear in extreme use.
Ive also had one girlfriend, and that was ok, but what was even better, was when I had two of them.
Elevated levels of ZDDP can actually be corrosive and cause damage, just like having two girlfriends that aren't aware of each other A stock ~13L diesel engine doesn't qualify under the same definition of extreme use as an 8,000HP top fuel engine that gets rebuilt every pass and subscribing to that philosophy is seriously flawed.
One of the most common oils used in 24hr racing events is M1 0w-40, which has ~1,100ppm Zinc/Phos.
OEM approvals and testing protocols actually validate the wear performance of the lubricant against applicable standards in tests that are designed to represent real world use so that people don't have to guess. Putting all your faith in the concentration of one additive is the reason people dump "ZDDP Super Concentrator 9000" in their oil and still lose camshafts. Oil formulation is a balancing act that's verified through testing and subsequent approvals, assuming you can infer the performance based on a cursory glance at a VOA betrays a fundamental lack of understanding of the subject and that process.
Down here in the south, our speed boats use the more common 25w-40 racing oils. 1551/ 1305 Zinc and Phos, right out of the bottle. Their TBN and formula should neutralize any corrosiveness for their respected numbers. But, the question remains, I asked for a recommendation on a motor oil, which will contain elevated anti wear additives, already in the formula. Based on your knowledge and experience, what would your suggestion be?
You aren't operating a speed boat though, lol. Those levels of ZDDP are similar to what's found in Mobil 1 15w-50, but that's not an oil rated for diesel use. And no, the TBN won't neutralize the corrosive nature of too much ZDDP.
Well it kinda is diesel rated - it has API CF certification
API CF was introduced for the service typical of indirect injection diesel engines, mostly used in off-road applications such as mining and construction. These engines use a broad range of fuel types, including fuel with higher sulphur levels.