Possible explanation of synthetic fuel savings and hp boost.

[dodge man]

An anti drain back isn't going to do any good for most engine parts. The oil is going to eventually drip off various parts no matter what. I thought that snythetic oil had pretty good cling properties, where it wouldn't run off parts, but I'm not sure about that. I would think in almost all vehicles, it's going to create less wear, but I suppose there is always an exception.

 

[Conservation]

The cling charictaristics are in the additive package that they use when making the oil...Dino or syn. If the syn cling performs poorly, then the cling additive is not doing its job.

 

[Redneck in training]

Now that is very interesting. Makes one wonder if those aircraft engines use oil filters w/the anti drain back valves.....

My F150 w/130K miles on it has only avg'ed around 50 -75 miles a week for approx the last 6 yrs now and I got concerned that the dino oil I was using may not provide the optimum cold startup flow that syn oil would offer so I changed over to it 15K miles ago (3 oil & OEM filter changes).
1st thing I noticed was the top end (4.6 SOHC) got quieter much faster. The rattleing/ticking went from approx 5 -10 secs to less than 5 secs and the engine seemed to run quieter as a whole in all temps. It doesn't use any more than it did before, approx 3/4 qt over 5k miles and it hasn't leaked yet so in my case changing over to syn improved my engines perfomance, at least at cold startup.

I never stopped to consider that syn would drain down more than dino but then again now that it's been mentioned I'm going to assume that thats what the anti drainback valve in the oil filter is supposed to stop. At least thast what I've been led to believe, but you never know

That is misunderstanding. It has something to do with exposing bare metal such in cylinders to moisture and causing rust spots. In example if the engines is not run for a months. Since the synthetic oil is less viscous it will run down from the cylinder walls exposing it. As opposed to mineral oil that stays on it especially when cold. I am not home now but when I return I will do an experiment. I will oil two pieces of metal in synthetic and mineral oil and hang them in the garage for a month to see what happen.