Mobile 1 makes a high milage oil gauranteed for 15000 miles.

 

They can gaurantee all they want....I don't drive a Porche or a Mercedes...I drive a Ford.....any type of oil breaks down eventually and all of them under certain conditions.....if you drive it like an old man than I'd expect it to last a little while.....I drive mine hard and I won't take chances....just a matter of preference....I highly doubt oil manufacturers take into account that someone like me with a 12 almost 13 year old truck would be using their oil... meaning...they probably don't produce it for older engine specs...just the newer ones.JMHO

JR

 

What's different about older engine specs? I go 5000 as Ford recommends in my owner's manual with plain old oil. I'd probably go at least 7500 if I was running synthetic. The 15000 miles has nothing to do with engine specs, but the ability of the oil to not break down like conventional oil. Any oil changes more frequently than 5000 miles on synthetic is a waste of money, no matter how hard you drive.

As far as break in period, if the rings haven't seated by the first couple hundred miles, something is wrong. Engines are well broken in by 1000 miles, so 10000-15000 before changing to synthetic is not necessary. Mobil1 says you can run it from the get-go, but I'm hesitant to do that.

 

Yea 10 to 15k would be a little over cautious but with regular oil changes during that period it really would hurt anything.
That was more of a quote from the article I read on it in car and driver written by or for one of the manufactures of oils. To run a fresh motor several thousand miles before changing oil types.

Yes the ring’s would/should be fully seated in the first thousand miles (The 500/500 break in). Unless the motor was ran improperly in that crucial period. Probably why the article said “several thousand” instead of several hundred just to be sure the rings did fully seat with any “average” driver behind the wheel before switching over to a synthetic type oil.

 

the warnings about using synthetic during break in, are for flat tappet cams and lifters not rotating in the bores like they should

of course now everyone is blaming the failures on low zinc content on almost all of the dino oils as well

 

Interesting reading, I am an A&P mechanic by trade. The way we run our piston engines after overhaul is to run a straight mineral oil until the spark plugs start coming out clean. (Grey deposits with no signs of oil on them). This can take from 50 to 100 hours. During the first 25 hours or so, the engine is ran at 75% power or better all the time except on final approach. The oil and filters are changed every 25 hours and the filters are cut open and inspected. After the plug readings are good, we switch to ashless dispersent oil for the rest of the life of the engine with oil and filter changes every 50 hours. I realize that aviation engines run in a steady RPM range and are much more looked after than automotive engines, but the same principles apply. Run the engine fairly hard on breakin, change the oil often and use low-detergent oil. After breakin, run whatever oil you want as long as it is a good quality. I prefer synthetics for the very reasons stated. They don't break down as bad as petro oils do, they have higher flashpoints therefore less boil off than petro oils. The oil molecules in synthetics are more evenly shaped and sized than petro, so the small molecules don't burn off faster as in petro. Not to mention, the more people that use synthetics, the less oil we have to buy from OPEC.

 

I wasn't referring to engine specs per se...rather the fact that over the years engine manufacturers have come up with better designs for engines and blocks.IE they disperse heat better and more continuously as well as flow better.......more and more vehicle manufacturers expect the vehicle someone is purchasing to be maintained with a synthetic oil so they would build to suit.How many vehicles did Ford produce 20 years ago that had aluminum engine blocks or other parts...not that many right?How many today are built with aluminum engine blocks heads and whatever?the majority...All I'm saying, and this is a matter of my own preference, is that oil makers are producing synthetics for a certain genre of engines...it's just not my genre.You keep your 15k mile oil......there is no such thing as throwing away money on the lifeblood of your engine if it's your main transportation(or only).Later...sorry for the long one.

JR

 

Check out this web page: http://neptune.spacebears.com/cars/s.../oil-life.html

I don't plan on running the full 15000 miles on the new long service Mobil1, but I don't think 7500 is out of the question, especially if those guys got 20000 out of the regular Mobil1 (based on oil analysis every 1000 miles). From a lubrication standpoint, an engine is an engine -- reciprocating pistons, journal bearings on the crankshaft and camshaft(s), and sliding friction on the cam lobes, lifters, pushrods, etc. If it gives you better peace of mind by changing synthetic on the same schedule as conventional oil, certainly do what you believe is correct.

As a side note, Mobil1 guarantees and warrants the engine against lubrication related failures for a year or 15000 miles when using their extended performance synthetic. They make more money the more often people change their oil, so why would they support extended oil change intervals? Must be some pretty good stuff.

 

I intend to change my oil every 5000 or less. I am also in the process of switching over to synthetic auto trans fluid, transfer case fluid, differential oil and greases. If I could get synthetic gasoline, I would do that as well. Then put a Calvin P#$%^&* on OPEC sticker on my truck. The Germans used synthetics in WWII and before quite successfully and we are just now starting to catch on. Maybe with the Fischer-Tropsch fuels coming on, we may see synthetic gasoline in the near future.