Steve,
I've looked at the BobOilGuy site a fair amount. I've noticed the viscosities of diesel
oil (5w40 and 15w40 - 5w cranks better in winter). Think about the pressures heavy duty diesel engines see and the
oil weight they use... I've noticed that the Ford 5.0 Coyote motor takes a 5w20 (for CAFE standards), but if you have the Track Pack mustang, it says 5w50 (I guess for track use). I think any clean
oil is better than any dirty oil. I own race cars, street cars that I drive hard, currently own an EcoBoost (Turbo) F150 and rather than get caught up in this stuff (as many on the Bob site do) I've come to a few conclusions:
If I'm picking one shotgun to own, it's a 12ga.
If I'm picking one oil to use for any weather, in all of my vehicles, it's 10w30.
If I know I'm driving the car at the track, I might like to pour in 10w40 (at Sebring in the summer).
If I have a pushrod motor with flat tappet cam, I'd run an oil with a lot of
zinc. Those have been created for a reason.
Otherwise, the only oil related problems I've ever heard about seem related to pressure, not type or brand.
Good luck.