My local Wal-Mart is a super store also and I checked a local Auto Zone
as well. The AutoZone didn't have ANY 5 quart jugs of Mobil 1, just
dino oil. Could be that Mobil isn't yet shipping the large jugs of
5W-20 until they are selling more of it, but the shelf was nearly empty
of the quart bottles of 5W-20 so I'd say sales are picking up.
You're right . . . I checked my local Super Wal-Mart, and they don't
stock the 5 quart jug of 5W-20 Mobil 1. I did find a "short case" (6
quarts) of 5W-20 at our local Blain's Farm & Fleet, but this store
chain is only in Illinois, Iowa, and Wisconsin.
I guess everyone will just to have to buy single quarts for the time
being. BTW . . . I checked with the Service Advisor and Service
Manager at the local Hyundai dealer, and they exclusively use 5W-30
weight oil. This, of course, is an OK alternative and listed as such
in the manual - at least it is in my 2006 Elantra.
One item of note: The wider the range of a motor oil, the larger
amount of V.I. (Viscosity Indexers) required. I was told by a
petroleum engineer here at the University of Illinois a number of years
ago that the greater amounts of V.I.'s used in motor oil, the greater
the propensity for varnish build-up and eventual sludging. I don't
know if this is a proven fact or not, but he's personally a great
believer in 10W-30 weight oil. It's generally good down to 0 degrees
F, and even my new Elantra Owner's Manual recommends this weight if
ambient temp is above 0 degrees F. In this case, 10W-30 Mobil 1 may be
just fine for most applications, especially due to its good
pourability, etc. at low temps, except where severe winters are the
norm. Just a thought . . .
I currently use 5W-30 in the winter (we often get well below zero here
in northern PA) and 10W-30 in the summer in my other vehicles and likely
will do the same with the Sonata, at least until 5W-20 is available in
the larger jugs.
Thanks for checking.
If the recommended oil is 5W-20, 5W-30 would work OK, but 10W oils would
not be recommended. The key is the weight of the base stock. 5W-20 and
5W-30 are made from the same 5W base stock. 10W oils are thicker and
won't flow as well. If the reason that 5W-20 is recommended is due to
tight clearances and small oil ports in the engine, a thicker oil could
cause oil starvation, leading to excessive wear and bearing damage,
especially if you live in a cold climate.
I'd have to re-check the manual, but I believe that all three weights
are OK to use given the right temperature range. 5W-20 is the preferred
oil, but I believe both 5W-30 and 10W-30 are acceptable.
Yes, all else being equal, 10W oils won't flow as well as 5W oils, but
all else isn't always equal. Viscosity numbers are given for a given
temperature (I forget the specifics now) and don't cover the behavior of
the oil at other temperatures. For example, a 10W dino oil will flow
the same as a 10W synthetic at only ONE temperature. At lower
temperatures, the more stable viscosity of a synthetic means that the
same weight synthetic will flow much more freely than the dino oil. My
10W-30 equipped minivan and truck crank much better at -10 than does my
Sonata with 5W dino oil.
You'll probably find that 10W oils are recommended for warmer climates
and summer use. I've never found any good reason to switch to thicker
oils in summer. As long as the upper end of the viscosity range is
adequate (the 30 in 5W-30) the heavier base stock isn't going to make
any difference and I'd rather have the better flow characteristics.
Out of curiosity, have you ever heard of anyone having an engine failure
due to oil that was insufficiently protective at higher temps (viscosity
breakdown)? It seems to be the thing most people worry about, but I've
never heard of such a failure. Using oils that are too heavy and cause
starvation seems to be a much bigger issue, at least in modern engines.
True. That's one of the reasons I use synthetic oils in my Elantra, both
in the engine and transmission. The transmission oil in particular makes
a big difference when temps are 0F or below.
Brand of oil is largely meaningless, since any oil that meets API specs
is going to last longer than Hyundai's recommended 7500 mile change
interval. That's doubly true of synthetics. Tests I've seen on synthetic
oils indicate that there's little practical difference between them.
Even Walmart's low-priced, house-brand "SuperTech" synthetic seems to be
as good as the big name oils. I've used it with no problems, though
lately, Pep Boys has been running specials on Pennzoil synthetic at
~$2/quart, so I've bought some of that.
I don't it bookmarked, but IIRC, I just did a search on "Supertech
synthetic oil test" or something similar and waded through the results.
I found the results from a testing lab that analysed it and gave some
conclusions based on what they found. Essentially, they said the base
stock is the same as many other brands (not surprising since the blender
makes oils for several other companies, including big name brands) and
the additive package is comparable to what other oils use.
When you get right down to it, nowadays, oil is oil. The differences
that companies tout in order to attract consumers are so small as to be
irrelevent. Modern oils are incredibly good. Just look for the API seal
and if an oil has it, it's more than good enough to put in your engine.
I would avoid oils that are not API certified, unless you're willing to
spend the money for Amsoil. I'm not.
I agree that most oils are good enough most of the time, but I disagree
that oil is oil. About the only independent and fairly comprehensive
test of oils that I've seen was done by MCN (Motorcycle Consumer News)
magazine. They have tested oils twice in the last decade or so and the
difference between the top and bottom oils is very dramatic, often 2X or
more in tests such as the ability to maintain viscosity, etc. Cheap
oils really are much worse than top rated oils. It may not make a
difference if you drive your car only 100,000 in easy conditions and
then trade it in, but if you drive 200,000 plus as I intend to (except
my last two vehicles got totaled at 143K and 182K), in a variety of
conditions from -20 to over 100, in the mountains, etc., then I'd rather
have the good stuff.
Please define "2X". It's extremely important to put the differences into
context. What are the tested parameters? What are the differences in
terms of actual durability in the engine?
There is also a substantial difference between the operating parameters
of motorcycle engines and automobile engines. In particular, motorcycle
engines routinely operate at rpms that are double that of car engines.
That creates very different stresses on oils. An oil that is "superior"
to another when used in a motorcycle engine may be no better in a car
engine, in practical terms.
In what regard? Specifics really matter here. Blanket statements like
that aren't helpful.
I see your point, but I'm not convinced that it makes any difference.
The length of time you intend to drive your car doesn't matter. What
does matter is how long you leave the oil in the engine. If you want to
push the envelope on oil change intervals (10K miles+), it makes sense
to use the most durable oil you can find. If you change your oil at
suggested intervals, any oil will last that long. That's been shown in
It's well know and accepted that that ~90% of engine wear occurs on
startup. Oils that flow better, such as synthetics, will help reduce
wear, as they get to all parts of the engine faster. However, if you
really want to extend the life of your engine, install a pre-oiler. That
ensures that the engine is fully lubricated BEFORE you start it. That
should make much more difference in wear and long-term durability than
one's choice of oil.
I don't have the magazine handy and I don't recall all of the parameters
tested, but it was things like TBN, levels of certain friction reducers,
oxidation reducers, etc. They provided bar graphs for all of the
relevant tests and the height of the best oils was twice that of the
cheap oils and sometimes even greater disparities.
There is no easy way to measure differences in engine durability in a
controlled way and it would cost millions to even attempt that. So, you
have to use surrogate measures.
They tested both car and motorcycle oils. There conclusion was that
most motorcycle oils weren't different enough from car oils to justify
the price premium. But it did appear that good oils were much better
than cheap oils. And synthetics were much better than most dino oils.
Call up the folks at MCN and buy a back issue of the magazine that
contained the oil test. I'm sure they will know which issue and can
sell you a copy. I can't remember the specifics from 5-6 years ago.
And you wouldn't believe me anyway so do some research for yourself.
Sure it matters how many miles you drive your car. If the engine wears
twice as fast using a cheap oil as a premium oil, then it will run half
as many miles. If the premium oil wear rate will let the engine last
250,000 miles, then the same engine with the cheap oil can be expected
to last only 125,000 miles. This isn't rocket science.
You say numerous studies, can you point me to one?
Again, any proof for your statement? I've heard this as well,
especially in the aviation industry, but I've also seen many counter
examples that suggest otherwise. For example, the airplanes that are
started most often and flown the least hours at a time are single-engine
trainers, yet their engines often last much longer than large singles
that are flown 2-3 hours at a time.
I've seen many suggestions that frequency of operation of the enigne is
more important than the number of starts and shutdowns. However, I've
seen NO data that supports either hypothesis, just anecdotal information
Hey Matt - can I jump in for a bit? Thanks.
While taking no exception to your point, I'd ask if that mysterious point of
diminishing returns plays in here. Conventional dino oil will do a fine job
of protecting a car and providing a 250,000 mile life expectancy with ease.
Folks like myself adhere to a 3,000 or 4,000 change interval and the concept
of dino oil giving this kind of performance is well established. Synthetics
are supposed to provide the same level of protection with half the oil
So my question is - is there really a useable difference between the premium
oils and a standard oil? Heck, what is a premium oil? Does that term imply
synthetic, or does it include dino oils with certain additives? I find it
easy not to argue with the notion that a super grade of oil will offer
longer protection, but my question really centers around whether that is
ever even noticeable in the life of a car. For the sake of conversation, I
assume the life expectancy of a car to be 250,000 miles. I have enough
experience getting this kind of life out of my motors with conventional dino
oil that it's no longer anecdotal to me.
Did I just stumble over a point that's already been covered in this thread,
and that I missed?
It well may. I use synthetic mainly for cold weather starts as I find
that my vehicles start much better and my batteries last much longer
using synthetics. I've gotten 8-9 years out of several batteries in
cars with synthetic oil and used to get 3-5 using dino oil.
From a wear standpoint, I believe there is a difference, but I agree
that it may not matter in the typical lifespan of a car. However, I
don't know that any data exists on this point one way or the other. I
have seen engines taken apart with well over 100K on them, and the
engines with synthetic oil are vastly cleaner than those using dino oil.
This may or may not matter, but if a chunk of sludge breaks loose and
clogs an oil passage, then I suspect that the synthetic oil will have
been much better. :-)
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