Another vote for the synthetic oil here, but for a different reason. Those of us in cold climates might experience slow cranking with dino oil in the winter. I've found that synthetic oils, in almost all applications, engine, transfer case, differentials, etc. just seem work better when the temp drops.
@Taco2Cruiser any thoughts on that?
I would agree with that’s statements. I just offer that with today’s API SN requirements, meeting specs, meets specs. So the difference in “feel” is just not what it used to be.
Today’s longer factory oil change intervals have helping bring synthetic oil cost down as it’s better on the environment to not change fluid as much.
But with that, API requirements have gone up to meet the demand of today’s engines. Which brings even Dino API SN oil at some pretty solid stuff.
Also, we need to look at the range of viscosities of these oils. And viscosity isn’t really the right term, more like pumpability. Within any grade of fluid, there is a range. Let’s just stick with motor oil for now though. A xW-20 oil has a range, and depending on the oil you buy, will be “thicker” or “thinner” (also not correct terms, but I’m keeping it easy).
So you got TGMO, which lives at the lighter side of the 20 weights, all the way up to Mobil 1 truck and SUV and RedLine xW-20s which lives at the heavier of the 20 weights. So on the edge of 20 weight that light 30 weights like Pennzoil Platinum Pure Plus 5w-30 is so close it’s not even funny. Same goes for Dino, they hang out on the heavier side. Which is why you probably like the older synthetics for cold starts. But looking at the oils available right now. You can buy a heavy 20 weight oil and a good 20 weight Dino oil and they will have some very close MRV (pumpability) specs and means the same to the average engine and daily duties that we put them through. Sure the Dino will loos it’s TBN faster, but that doesn’t make it worse, just needs to be changed more frequently, and since it’s cheap, you can afford to change it more often.
Moral of the story, run whatever you want, we’ll never be able to find an oil that is a little more better than all the oils that are already more better than needed. And sleep easy at night.
This is also coming from a guy who can’t stop thinking about this stuff and longevity.