Should I really pay 5 dollars for on quart of oil. What is so good about Syntec oil???
Well, I have to start working in a few minutes, so I’ll just throw in my 2 cents worth:
I think synthetic oil is able to keep it’s viscosity (thickness) constant, unlike mineral (petroleum) oil that eventually breaks down and produces by-products which are harmful to the engine internals. THAT would explain why you have to change one more than the other. In fact, it works SO well, that they don’t recommend you use it when breaking a car in. It coats the parts, and actually forms a layer that doesn’t allow the metal parts to seat in properly. Should stay mineral for a year or so, and then go synthetic… just IMO BTW.
Okay, I think it’s time G2IC has a copy of this in its archives… great article.
Ok… so here’s info from a friend named Phil Hall… he studies lubricants at NASA. I really don’t think there can be a better source of unbiased info AT ALL… I’ll break this up into several posts here… and then eventually add it to the FAQ (or maybe ask him to write up something more technical for the FAQ)
PART 1:
Today’s topic seams to be motor oil related. I am a NASA Engineer at
Marshal Space Flight Center in Huntsville, Alabama. My field of work is
Tribology which is the study of friction, wear, and lubrication. In our
spare time, our group collects and tests different motor oils using the
Shell Four Ball tester. This tester tests the extreme pressure properties
of oils. These areas in a motor are cam to lifter contacts, valve stem to
guild, and piston skirts. Over the years we have found synthetic bases oils
to out perform mineral based oils by a large margin. We test the oils new,
after 1000 miles, 2000 miles, and up to 10,000 miles. In a nut shell, we
found that synthetic oils have better wear properties after being run 10,000
miles then mineral grade oils new. Which synthetic do we use? First any
you will benefit from any synthetic, but we use Mobil 1. Mobil by far puts
more research dollars in motor oils then any other company. They are also
aggressive in racing.
Other notes on motor oils.
Do not run a multi grade oil (10w-30) more then 1000 to 2000 miles -
depending on your driving habits.
This is because a 10w30 oil starts its life as a 10 weight oil and large
polymer chains are added to get the 30 rating. These chains break down very
quickly which produces small chains with an open electron charge at the
ends. These ends attract grim and form sludge.
Do not run synthetics in a new rebuild. A new engine needs the added
friction allowed by mineral oils to set the rings properly. Chevy found
this out on the corvette. These cars came from the factory with Mobil 1 and
owners brought them back because of smoking and oil consumption (rings did
not seat). Run a good single weight oil for the first 2000 miles. We found
Havaline 30 to be a good mineral oil - in fact we use it for our standard.
The reason Mobil 1 can safely be run for 10,000 miles is because the
additive package is well engineered to isolate grim and hold it in
suspension. This also is why Mobil 1 is expensive. You know - you get what
you pay for.
I know there are a lot of questions on motor oils. You can e-mail me for
more information or search the web for more details on synthetics. Your
Roadster deserves the best - run synthetic oils.
Phil Hall
Part 2:
I listed multi grade oil break down at 1000 to 2000 miles. This is for the
junk oils found at circle K for a dollar. A good name brand oil will last
3000 miles without too much break down. This is for mineral grade oils -
synthetic oils meet government viscosity tests for ratings without adding
thickeners like polymer chains.
Guys here at work run synthetics in motors that have 140,000 to 170,000
miles on them without any more oil consumption them normal. I believe that
you will get a slight increase in consumption in older motors because the
synthetic are very slippery and can get by old rings easier. In these cases
going to a 15w-50 may help, but this is not a reason not to use synthetics.
Older motors need the extra protection. At running temperature a synthetic
will maintain its viscosity, where a mineral oil viscosity is DRASTICALLY
REDUCED.
A test on how well synthetics work at different temperature can be done in
your home. Get a quart of your favorite mineral oil and a quart of a
synthetic. Put a cup a each oil in a glass or paper cup and stick in the
freezer over night. In the morning try and pour the oils out. Next test:
DO THIS OUTSIDE. On an old camp stove put a ¼ of the synthetic oil in an
old frying pan and put it on the stove on the highest heat setting. Cook
for 30 minutes. Now cook your oil for 30 minutes. At this point you will
see why you cooked the synthetic first. As the oil cooks pour some out to
see the changes in viscosity between the oils.
Part 3 on oil additive coming soon. I need to back to NASA work.
Phil Hall
Part 3:
The question of change intervals and synthetic oil has come up. As a side
at work we run oil tests using the Shell Four Ball test rig. This tester
was developed by Shell oil to test the extreme wear properties of motor oils
- cams, piston skirts etc. It consists of three, = inch balls held in a
triangular pattern in a cup with oil heated to 165 degrees. A forth ball is
lowered to the center of the three balls and loaded to 40 KG. The ball is
then rotated 600 RPM for one hour. After the test the wear scar is measured
on the three stationary balls. The bigger the scar the lower the extreme
wear property of the oil is. We use Havoline 30 wt for a base line. We use
this oil because engineers from the past liked this oil, so we have a large
data base.
Looking at data shows new Havoline 30 wt has a wear scar of .0165 inches.
New Mobil 1 has a .0145 inch scar. May not seem like a lot of difference,
but it is. Havoline 30 at 3000 miles has a wear scar of .020 inches and
Mobil 1 at 4000 miles has a .0164 scar. Remember - the bigger the badder.
3000 miles is as long as anyone was willing to run Havoline 30 wt, so its
data stops here. Mobil 1 at 6000 miles is .0167, at 8000 miles is .0188,
and at 10,000 miles is .0194. So, at 10,000 miles Mobil 1 has better
lubrication properties in the critical areas in your motor then a good 30
wt. All mineral oils follow Havoline pretty close - major brands. Some off
brands have a .020 wear scar new. Multi-grades generally have a larger wear
scar as well. This data was from a 5.0 Ford Mustang. Every motor will be
slightly different, but not much.
So, synthetic can handle long run intervals. But, that is part of the
story. You have contaminates to deal with. This is where the additive
package comes in play. This is the expensive part of oils and the reason
synthetics are high priced. Because of the long run intervals of synthetic,
they must have a vastly superior additive package - and they do. Proof of
this is to take 3000 mile dino oil and look at it in a glass jar - then do
the same for Mobil 1. The Mobil 1 will look new compared to the dino oil.
I run Mobil 1 in my new cars to the longest manufactures oil change interval
- usually 7000 miles. This will keep the warranty happy. In my Roadster I
change it once a year regardless of mileage. It run my Roadster about 5000
miles a year. Most people at work run synthetics and do the same. We have
a bunch of cars in the lot that have over 200,000 miles on them and going
strong. I (my wife) never keeps one that long.
I run 10w-30 Mobil 1 in my new Roadster motors (after break-in). Older
motors get 15w-50 because the tolerances are larger. Because synthetics
don’t thin down like mineral oils do at temperature, I would be careful
running 15w-50 in a motor with a high volume oil pump. By doing so you may
run into cavitation problems - oil gage jumping wildly. Drag racers
experience this often at high RPM. Drop a wt and it will clear up.
I checked the auto parts stores last night and could not find a zero wt
Mobil 1. It was about 2 years ago they were talking introducing this oil,
so apparently they have in some markets. I stand corrected.
Testing another “magic” oil additive today. It looks and smells like
linseed oil! This should be fun. Additives are another subject all
together. Another day, but never tested a good one - none- zip - zero -
don’t waste your money.
Sorry for being soo long. I like synthetics (obviously). If you have been
to the conferences, seen all the tests and data, and read the lubrication
journals you would run nothing other then synthetics.
Phil
very interesting… it makes me wanna go out and convert. however i have 165k and burn about a quart a month. maybe i should take the risk of leak and try it? i do drive hard…
so im thinking if it ends up leaking, at least my engine will be better protected under harsh conditions… 1-2 synth bottles lossed/burned a month if it leaks… 10bucks…
however if it doesnt leak, ill have protection as well as less burning.
now what if it leaks and i want to go back to mineral? will it seal again? maybe it’ll take a few months for it to sludge and reseal… ill consider doing this at my next change. wish me luck =P
I don’t think anyone mentioned it yet, so archivethis
With 284,000 KM on my car (about 200,000 miles), should Istart running synthetic or semi-synthetic? I have a small leak (I think) in the oil pan, which loses about a quart every 6 weeks or so.
Would switching to semi or full synthetic be more prone to leaking? But, maybe the synthetic will help prolong my engine life, especially in the hot summer months?
Any advice GREATLY appreciated. TIA! 
~Eric
Well, i’m breaking in right now (1500 kms on rebuilt LS). Should I go with 5w-30, 10w30, or not use multi-grade?
curls: If you’re leaking, don’t switch to synth yet. Get the leak fixed. If anything, synth will make it worse.
smokInteg: If you read the article, it suggests using plain ol’ regular mineral oil for new and rebuilt motors. LS’s generally like 5W-30. So stick with the mineral oil until break-in is complete, then switch to synth if you like.
Even though Phil Hall’s statements are very insightful, if you change your oil religiously every 3000 miles, there is nothing wrong with regular mineral oil. Motors do tend to hold up better in road-race cars with Mobil 1 synth… this, I have observed. If you just do an occassion auto-x/trackday/whatever and the rest of the time, your car is a daily driver, I wouldn’t consider it a race-car.
Originally posted by ryank
Even though Phil Hall’s statements are very insightful, if you change your oil religiously every 3000 miles, there is nothing wrong with regular mineral oil. Motors do tend to hold up better in road-race cars with Mobil 1 synth… this, I have observed. If you just do an occassion auto-x/trackday/whatever and the rest of the time, your car is a daily driver, I wouldn’t consider it a race-car.
really? i wouldve considered just driving like a maniac on the street is enough to worry, let alone an occasional autox/track. i even have an automatic and consider my street habits to wear down the motor at least 5x faster than the average driver who rarely ever even breaks 3k rpm heh
Originally posted by XDEep
[B]
really? i wouldve considered just driving like a maniac on the street is enough to worry, let alone an occasional autox/track. i even have an automatic and consider my street habits to wear down the motor at least 5x faster than the average driver who rarely ever even breaks 3k rpm heh [/B]
Auto-Squad(HA!)
I’m with you on that!! People say, you don’t need to upgrade your brakes if you don’t race. But if you drive your car like its a race car (even if its automatic like mine and XDEep) then you should!!
Originally posted by ryank
LS’s generally like 5W-30. So stick with the mineral oil until break-in is complete, then switch to synth if you like.
Tell me. How do you know that the ls likes 5w-30. what about the gs-r motor. i’m sure that is the same, however you made it sound as if the ls likes different motor oil than the rest.
Also, another question. Since I’ve only had my car a few months, I have changed the oil only once. When i had the oil changed professionally, i was not aware of synthetic oil. Do we have the option of having the pros put in synthetic oil in our motors at an oil change, as opposed to ‘regular’ oil???
Katana: If you live in moderate climates and are using regular mineral oil, the owner’s manual will show that 5W-30 is probably best for the non-GSR’s… and 10W30 for the GSR. This isn’t set it stone, but it is what is recommended.
At oil change places, you can specify synthetic, but they usually charge you thru the nose for it.