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Discussion Starter · #1 ·
Picking up on a thread farther down the line, I am amazed at the polarization of opinion on the synthetic issue. People either think it's crap or the nectar of the car gods. My experience is that synthetic does not break down as readily in high heat situations (such as turbos) and in fact seems to thicken a bit instead of thinning like 'natural' oil does in those situations.

And as for the so-called 'tests' done on synthetic that claimed it didn't work any better, they missed the point. Run two engines continuously until they frag and I guarantee the non-synthetic one will go first.

Anyone who doesn't think it lubricates better, ask an engine shop what kind of oil they recommend for engine break-in. All the ones I've ever dealt with say regular oil. And ALL of them say specifically NOT to use synthetic. Why? Because its lubrication properties are so good the rings won't seat.

The only three disadvantages to synthetic are that it is expensive, it does tend to break down natural oil deposits in older engines -- and therefore should be changed sooner when you first switch over to clear all that crap out. (By the way, if any of you have ever torn down a worn out engine that has been run with synthetic, you'll know it's pretty clean inside, not full of all that sludgy crap that's in the natural-oil engines.)

The third thing is that synthetic does make an older engine seep more. IMHO, it's definitely worth a few extra bucks.
 

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Discussion Starter · #2 ·
<b>RE: Synthetic Oil True Story</b>

A buddy of mine has an old Landcruiser, he was beibg transfered to Germany last year (Military). He thought that since the engine had 180 Thousand miles on it he'd better tear it down and rebuild it before the move. He had used Mobil 1 since it was new. He tore the engine down and dropped of his block and crank at the local machine shop. They called him 2 hours later, and told him everything was within specs..no need for machining. I was impressed, but I do think you can have similar results with regular oil if you keep it clean.
 

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Discussion Starter · #3 ·
<b>Synthetic Oil & Taxi Tests</b>

testing oils in taxis is just not a real world scenario. taxis are driven completely different than a real world every day car. taxis idle for hours at a time. sometimes they'll run for two or three shifts without ever being shut off. i've taken cab rides in chicago and new york, and the cars sit at stop lights more than anything else. when they are moving, they rarely see more than 3,000 rpm. the problem with comparing taxi engines is they're always hot. the crap is always being burned out of the oil, so it's clean, and they don't go through expansion and contraction periods like a real world car does. think about your own car. you start it dead cold in the morning and everything expands, you get to work and it cools down and contracts, and then you do it all over again on the ride home. if you drive your z like i do, your motor sees redline a couple times a day also. i went to tech school with a guy who worked for yellow cab. he said a taxi motor such as a 350 chevy or a 360 mopar or even a ford could see half a million miles on the motor without ever needing a rebuild. he also said that a lot of these taxis never had a chance to cool down. they'd get shut off for 10 minutes during a shift change or during fueling. the only downtime for these cars is during maintenance and repair. under these conditions, taxis rarely see a cold start, are always maintaining temperature and therefore mechanical clearances. it stands to reason that it may take a couple hundred thousand miles of driving a taxi to see a difference in engine wear between two different oils.

i've been using mobil 1 for almost a year now and i've noticed the difference. my engine runs quieter, smoother, and stays cleaner. i feel that a couple bucks a quart more for oil is no big deal, especially if it saves me time and money in the end. i always buy the best parts i can get for my z, so why not buy the best oil?

from my experience, operating rpm of your engine plays a huge difference in engine wear. i broke the tranny in my old z, it had no 5th gear. knowing what i do about trannies, i knew i could keep driving it this way for quite some time without any more problems, for the damage was already done. i drove to seattle every day, about 60 miles one way, at 70 to 80 mph in 4th gear with a 3.90 diff (about 4,000 rpm). i put 35,000 miles on the car under these conditions. i used conventional valvoline in the car. before the tranny episode, i burned maybe half a quart of oil between changes. after 35,000 miles of high rpm driving, i was using 3 quarts between changes, and it was all going out the tailpipe. if you're going to compare sythetics to conventionals, test them at higher rpms, where a sports car would operate. the rate of wear is greatly accelerated under high rev conditions. that's why race cars have all gone to synthetics. and if you really want to see the difference between the two types of oils, pour some redline synthetic in your gearbox.
 

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Discussion Starter · #4 ·
RE: Synthetic Oil & Taxi Tests

gotta agree-synthetics are the way to go.
EVERYONE knows; cold startups is where 90% of your engine wear happens-before the oil pumps up to pressure.
 

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If synthetic is so great why is mineral still sold

It would seem if synthetic was so superior, mineral based motor oil would be obsolete and automakers would use it. I have yet to see bonified proof it is superior in a street motor. It's gonna take more than some unsubstantiated "I knew a guy" or "my car seemed faster, quieter etc" story to convince me (and I've read plenty of Amsoil's propaganda). And lastly - can anyone tell me why synthetic costs more? The petroleum engineers I know all say it shouldn't now that the manufacturing processes are refined (no pun intended) - could be we have a conspiracy going on here.
 

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Discussion Starter · #6 ·
RE: If synthetic is so great why is mineral still

My 94 Corvette came from the factory with a synthetic motor oil, Mobil 1. It requires the use of it to maintain warranty coverage. Also the tests that were shown to me by the Chevy dealer on valvtrain wear over 100,000 miles for standard oil vs. synthetic (Mobil 1) were quite impressive. The valvetrain wear on the engine (LT1) with synthetic was still within factory specs. and the other engine (also an LT1) had "normal" wear. (No longer within factory specs and visibly worn)

As far as replacing non synthetics, it probably will eventually. The cost is coming down for production, but consumers tend to shy away from obvious benefits. Instead most consumers prefer to believe the duralube infomercials. ;-)

Another thing to keep in mind is that the use of pure synthetics in all new cars would cause a huge financial loss for auto parts manufacturers, mechanics, etc. that depend on parts and engines wearing out prematurely. It is kind of like the light bulb, we can buy a light bulb that will probably outlast us, but we typically buy the ultracheap 4 pack 100 hour bulb. That just seems to be the average American mentality.

Do you understand why synthetics are better? Do you think that synthetics are "synthesized" as in not made from petroleum? I have seen others with these ideas. Synthetics are specially refined oils in which all of the hydrocarbons are the same. There are no impurities and long or short hydrocarbons. This allows the oil to be much more predictable and longer lasting.

Well, enough preaching.

Rev. Green
 

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RE: If synthetic is so great why is mineral still

I agree the chemical and lab tests show synthetics to be more stable and superior (perhaps this is what justifies the cost difference). BUT in the average street motor I question the REAL benefit. I've seen a lot of high mileage motors run on mineral. If you are running a hot or modified motor the difference becomes more important.
 
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