Mobil 1 makes a 5-30 a 10-30 and a 15-50. I'm not sure what's best to use during a track day. 5-30 seems a bit thin, but 15-50 seems like overkill. Would mixing the 5-30 and 15-50 equal a 10-40? and would it be a good idea for the track? Sorry if this is a dumb question, but for those with an answer, thanks.

 

I'm pretty sure there is a Mobil 1 10-40.

Doesn't answer your question...but it's the best I can do.

 

hey tunes, just buy my oil, 10w60. it doesn't burn at all....seriously

 

don't use a 5w oil in the hot weather.........use 10w30 or 10w40........either one will work fine. If your car is basically stock use the closest to the manufactures recommendations...........but don't use a 5w whatever ........

 

I would like to use mobil 1 10-40 but I'm almost positive that they don't make it. That's why I wonder if it's ok to mix 5-30 and 15-50 half and half to get 10-40.

 

Hmm...that's strange. I could have sworn I've used it before. I'll hunt around my garage for an empty bottle.

 

don't mix......Amsoil makes 10w40 (better than Mobil 1).....if you can't find it where you are...i am a dealer and I can sell it to you...........

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Maxx44 &raquo;</TD></TR><TR><TD CLASS="quote">don't use a 5w oil in the hot weather.........use 10w30 or 10w40........either one will work fine. If your car is basically stock use the closest to the manufactures recommendations...........but don't use a 5w whatever ........
</TD></TR></TABLE>

I was always under the impression that the number 5 in 5-30 meant that it was thinner during startup. Why would this matter during a track day? Wouldn't the second number, the 30, be of more importance?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Maxx44 &raquo;</TD></TR><TR><TD CLASS="quote">don't use a 5w oil in the hot weather.........use 10w30 or 10w40........either one will work fine. If your car is basically stock use the closest to the manufactures recommendations...........but don't use a 5w whatever ........
</TD></TR></TABLE>

This is absolutely false info here. If you go and look in your owners manual there is a chart that shows viscosity vs. temp. 5w30 is recommended for the full temp range (unless you live in north Dakota or the like.) Again, like everyone has posted 23 million times on this board, once the oil is hot, the first number is irrelevant. 5w and 10w30 hot is the same.
Mobil DOES make a 0w40 that is sold at Auto Zone. I know this because I picked up 4 qt. a few days ago. I am going to put it in before my track event that is coming up in 2 weeks.

I actually have the same question you posted: Is it ok to fill the car with 4 qt. of Mobil 1 syn. 0w40, then top off the other ~.5qt with some Mobil 1 syn. 5w30?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by siisgood00 &raquo;</TD></TR><TR><TD CLASS="quote">5w and 10w30 hot is the same.</TD></TR></TABLE>
Well, close enough for arguements sake.

 

here is my source.......go to the bottom and find the posts about oil
http://www.angelfire.com/ar/dw42/

this guy knows more about oil and such than most people should..........

please don't forget that the reason the manufacture uses a 5w oil is because the car has to pass stringent emission regulations not because they care.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eee Pee &raquo;</TD></TR><TR><TD CLASS="quote">
Well, close enough for arguements sake.</TD></TR></TABLE>

No, its not. I was referring to the comment, "dont use 5w whatever"

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Maxx44 &raquo;</TD></TR><TR><TD CLASS="quote">please don't forget that the reason the manufacture uses a 5w oil is because the car has to pass stringent emission regulations not because they care. </TD></TR></TABLE>

So why do most european cars require 40 weight oil? They have to pass the same regs here in the US.

Also, honda also says 10w30 is an alternative to the 5w30 which is recommened.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by siisgood00 &raquo;</TD></TR><TR><TD CLASS="quote">No, its not. I was referring to the comment, "dont use 5w whatever"</TD></TR></TABLE>
Sorry, what I was meaning is that a 5w-30's 30 weight is close enough to a 10w-30's 30 weight. Like you are saying.
But usually they aren't the same exact Cst @ 100C (210F).

 

Synthetic Oils
dave williams
rec.autos.tech 12-08-92
- Basically, synthetics are tougher, lubricate better, and you can extend your
oil change intervals slightly. You still have to change the oil, because
the synthetics' additive package fills up with water from condensation and
general crud from blowby, just like regular dinosaur fermentings.
- Modern, name-brand SG rated oils are *much* better than the stuff of just
fifteen or twenty years ago. They're better than some of the earlier
synthetics. They're more than capable of dealing with your average
automobile's lubrication needs, particularly WHEN CHANGED AT REGULAR
INTERVALS. I'd lay money half the cars in America hit the junkyard with the
same oil they left the factory with.
- Anyway, if you're pulling a trailer, drive very hard, or have a turbocharged
or supercharged engine, or are just plain paranoid, a synthetic oil will
give you a little extra edge, but it won't work miracles. If you can afford
it, go for it.

dave.williams@chaos.lrk.ar.us (Dave Williams)
italian 21 Mar 1994
- -&gt; engines, then changes the oil to synthetic (another debatable
-&gt; topic-breakin on synthetics) and puts in another filter.
- Debate? You want debate?. I talked to TRW, Perfect Circle,
Hastings, and Total Seal back in January. The word from the people who
make the rings - don't try to break the engine in on synthetics or
you'll have trouble getting the rings to seal. They recommended
starting with a good brand of dino oil and going to synthetic at 100 to
500 miles.
- When I asked about the Corvette ZR-1 and the Cadillac Northstar, the
Perfect Circle tech said "yes, I know they're doing that, but it's still
not a good idea."
- All four reps agreed that the rings would eventually seat with
synthetics, and that moly or ceramic coated rings might not have
problems, but why tempt trouble?

dave.williams@chaos.lrk.ar.us (Dave Williams)
italian 23 Mar 1994
- -&gt; regular on the other- you can feel the slickness difference. In jet
-&gt; engines, they change the oil only during rebuilds, I'm told, just
-&gt; change the filters regularly and test the oil for metal particles.
- True, but turbines aren't subject to anything like the abuse piston
engines can do to their oil. They typically run for long periods of
time, don't have any unburned fuel or blowby contamination of the oil,
and the combination of heat and altitude minimize water contamination.
(water/oil/heat generates acids that attack many bearing materials)
- Big engines - mobile and stationary Diesels, that sort of thing - often
go for oil analysis instead of a regular change interval. But you're
talking about maybe 50 quarts or more of oil, where the $10 to $30 fee
for oil analysis starts looking pretty good. You can buy five quarts of
dino oil and a filter for about $10; I couldn't find any place what
would do an analysis cheaper than that. I'd just as soon have nice
fresh oil.

dave.williams@chaos.lrk.ar.us (Dave Williams)
italian-cars list 07 Apr 1994
- -&gt; Are all synthetic oils created equal?
- Um. As a matter of fact, no. There are some substantial differences
in the base compositions. On the other hand, for street and even most
racing uses, there's not enough difference to concern yourself with.
- -&gt; (part dino oil, part synthetic)
- There's nothing wrong with para-synthetic or synthetic-boosted oils
unless you're dealing with something like a very hot drag motor that's
at the limits of effective lubrication to begin with, or are trying to
stretch change intervals past 10,000 miles or so.

dave.williams@chaos.lrk.ar.us (Dave Williams)
fords 02 Aug 1994
- -&gt; Red Line uses polyol esters, Mobil One is composed primarily of
-&gt; polyalkylene esters.
- Red Line is pretty much the odd man out now. Most of the modern
synthetics are PAO based like Mobil 1 as far as I know.
- The "Shake Well Before Pouring" on Red Line's bottles pretty well
turned me off right from the start, though a friend has used it without
any complaints. Maybe it was just an artwork hiccup.
- Back in the early '70s through the mid'80s there were at least a dozen
startups selling synthetics. You'd see glowing reviews in Popular
Mechanics or whatever, then they'd drop from sight. Some were probably
okay products doomed by marketing, but at least a few were repackaged
aviation lubes and not too great for automotive use. Mobil 1 was the
only synthetic widely available. Others, like Amoco's Ultimate, have
been around almost as long, but were packaged and marketed only to fleet
buyers.

dave.williams@chaos.lrk.ar.us (Dave Williams)
italian-cars 06 Aug 1994
- -&gt; Seriously, do remember that oil - even synth oil - is a petro
-&gt; product,
- True. PAOs such as Mobil 1 are made from natural gas. Polyols like
Red Line come from various sources, sometimes cracked petroleum.
- -&gt; and the US is an oil exporter, not an importer,
- False. The US of America imports. After WWI the War Department
realized the future of warfare lay with mechanized infantry, which in
turn depended on petroleum products. America's best oil fields were
brought under government control and are military reserves. The tax
structure was then juggled to make it more attractive to burn someone
else's oil instead of our own, which is fine military strategy even if
it isn't Mr. Nice Guy politics. We still pump lots of our own oil,
though. More than we used to. Twenty years ago there was this little
problem with something called OPEC...
- -&gt; besides which oil and gas are heavily subsidized here.
- False. There are no subsidies on oil and gas in the USA; de gummit
just taxes gasoline at 100% or so instead of 300% or more like some
other places. Fuel "oils" are taxed at varying rates depending on their
intended use, and frankly I have no idea how lubricating oils are taxed.

dave williams
08-06-95
- -&gt; &gt; Synthetic oil is too good of a lubricant during break-in
-&gt; &gt; causing the rings to not seat properly.
- -&gt; I believe that this is an old wive's tale. While the process may
-&gt; take a little longer, rings and valves still seat themselves.
- Last year I spoke with various engineers at TRW, Grant, Hastings, and Total
Seal. They all specifically warned against the use of synthetic oil for new
engines. All the ring makers have tech support people available; all you
have to do is call and ask to speak to one.
- -&gt; Chevy Corvette LT-1 and LT-5 engines are broken in with Mobil 1.
- When I asked about that, the TRW ring tech said, "Yes, I know they do that.
It's still a bad idea." You may also be interested to know that GM says
the LT-1 and LT-5 must use more than one quart of oil every 500 miles before
they will perform warranty service on the problem. That's not quite
mosquito fogging, but most people would consider that as quite high oil
consumption.

dave williams
08-06-95
- -&gt; Mobil makes a fine product, but Amsoil was the first company to
-&gt; develop a 100% synthetis API rated engine oil way back in 1972.
-&gt; Mobil did not come around till 1975. Amsoil pioneered synthetic
-&gt; lubricants for cars and trucks... not Mobil.
- Oh, my. What interesting propaganda. Standard Oil of Indiana did the first
development of synthetic oils back in the 1930s. The Germans built upon it
during WWII after the Allies successfully interdicted their oil supplies.
Development continued more or less unbroken as Paperclip scavenged the
program for the US jet engine projects. By the late 1940s there were a
number of commercially available synthetics, mostly diesters, aimed at the
aviation market. The military has used synthetics for polar-environment
land vehicles since the 1950s.
- During the 1960s a number of synthetic oils hit the market, mostly
repackaged aviation oils. By the early 1970s some companies were making
their own, or buying base stocks and developing their own additive packages.
All Proof, Love, and Freedom were some of the early brands.
- No, AmsOil didn't pioneer any oil technology, though their MLM marketing
scheme evidently uses some nifty mind control techniques.

dave williams
08-06-95
- -&gt; Steve I have saved close to $1,000 over the past 4 years using
-&gt; Amsoil synthetic oil in my engine from the improved fuel economy alone.
-&gt; Petro oils? Thanks, but no thanks...they cost me too much money!
- You must be racking up an awful lot of mileage. Most figures show the
average driver does about 12,000 miles per year.
12,000 * 4 = 48,000 miles
Other figures show the average car gets 20 mpg.
48,000 / 20 = 2400 gallons
SWAGging an average of $1.15/gal over the last four years:
2400 * $1.15 = $2,760 in fuel costs over four years.
$2,760 / $1,000 = .36, or 36%
- You got a 36% increase in gas mileage, or (using Mobil's 3% improvement
figure) drove about 125,000 miles per year to save $1,000.
- I'd like to see your numbers.

dave.williams
rec.autos.tech 08-13-95
- -&gt; of them. Realize that Mineral Oil products are simply distilled from
-&gt; the crude oil that is pumped from the ground. Synthetics WASTE
-&gt; NATURAL RESOURCES because a great deal of precious energy is consumed
-&gt; in producing them.
- Simply distilled, eh? Not hardly. The output of fractions suitable for
lubricating oil is small, which is why a good deal of effort goes into
developing viscosity improvers for lighter fractions. Even with the
fractions of suitable grade, considerable work is done to remove paraffins,
sulfur, and other undesirable contaminants. The energy input to do all this
is nontrivial.
- Though there are other processes, the most common method of generating
synthetic oils starts with natural gas. Yes, children, "synthetic" oil
starts out as hydrocarbons in the ground, just like ordinary oil. The
difference is, rather than cracking and purifying random hydrocarbon chains,
synthetics are built up from short, simple molecules. The overall
difference in "precious energy", from source to shelf, is negligible.
- -&gt; producing them. AND FURTHERMORE NO ONE CAN USE THEM LONGER AND
-&gt; STILL HAVE A GOOD ENGINE THAT WILL LAST AND LAST.
- It is my opinion that most automobiles sold in the US hit the junkyards with
the same oil the manufacturer filled them with, plus a few quarts of
whatever was cheapest when the poor thing started to rattle after the oil
light came on. Many of these engines *still* pass the 100,000 mile mark.
Still, *any* oil change, regardless of brand or type of oil, is preferable
to eight year old sludge.
- -&gt; As for turbos - the oil that I use is designed to work in DIESEL
-&gt; ENGINE turbos - an environment that is at least as severe as auto turbos.
- The additive packages for Diesel-rated oils vary quite a bit from the
packages for gasoline oils. That's why the API has a whole different rating
system for Diesels. Diesel oils typically contain lots of nice high
pressure additives like zinc dithiophosphate, which makes gas engine
catalytic convertors unhappy. Gas engine oils have additives to absorb
combustion byproducts that do not exist in Diesel engines.
- -&gt; BUT DO NOT USE A 5W oil in hot weather. I know that the auto
-&gt; manufacturers recommend it - but THEY do not worry about your engine
-&gt; wearing out - they will sell you another car - THEY ONLY WORRY THAT
-&gt; THEY CAN CLAIM THE GOVERNMENT REQUIRED FUEL ECONOMY and 5W oils give
- The EPA requires autos sold in the USA to meet their emissions spec at
50,000 miles, soon to go to 70,000 miles. If your engine wears out to the
point of failing emissions, the automaker will have to replace it, for free,
unless they can find a way to weasel out by claiming abuse or improper
service. I'd say the automakers have a stake in how long the engine lasts.
Besides, in most parts of the country, the car will be wrecked or rusted out
long before the engine fails anyway.
- -&gt; people, the opinions of people who like to waste money and the,
- Locally, a name brand mineral oil costs $1.50-$1.85 per quart. Mobil 1
synthetic and some of the para-synthetics run $3.50 per quart. A dino
change costs me about $11.75. A synthetic change costs me $20.50, or
roughly double. This is quite favorable compared to 1980 prices, where dino
oils were 69 cents and synthetics were $8.00. With a 3000 mile drain
interval, you're looking at 33 oil changes in 100,000 miles. That's $390 for
dino, $676 for synthetic. The price difference is $286, which is trivial
over the operational lifespan of the car.
- -&gt; I have seen pictures of the underside of pistons (undercrown areas)
-&gt; comparing the deposits from a leading synthetic against a very high
-&gt; quality (but still much less expensive) mineral based oil. The
-&gt; synthetic left severe deposits in just the course of a race - the
-&gt; high quality mineral was nearly clean.
- Hmm? Who cares? What did the *bearings* look like? How about the
camshaft? Does this test come out the same for street vs race use?
- -&gt; BTW a synthetic piston aircraft
-&gt; engine oil had to be withdrawn from the market because it left severe
-&gt; deposits in engines.
- What brand? When? Enquiring minds want to know.
- -&gt; Steve Eisenstein, PhD
-&gt; Lube Specialist for a Major Oil Company
- Major Oil Company, eh? With your level of expertise, I can see why you'd
want to avoid embarrassing your employer.

dave.williams
rec.autos.tech 08-13-95
- -&gt; Oil does not wear out - the additives and acid neutralizing
-&gt; capability DO WEAR OUT.
- Oil is composed of various long-chain hydrocarbons. Its viscosity and
lubricating ability depend on the way these long chains slide over each
other.
- Ordinary mechanical shear from the engine's operation breaks these chains,
reducing the oil's ability to carry load. Combustion byproduct
contamination generalls causes an oil to thicken with age, but by this time
the chains are very short and the oil has little load-carrying ability.
- -&gt; Using a high quality mineral oil in my 4 cars (3 over 100,000 miles)
-&gt; and protecting the environment from the excessive use of natural
-&gt; resources to manufacture synthetic oils.
- Why don't you go off and save the gay whales for Jesus, or something?

 

Good read.
Who is Dave Williams?
Ever visit http://www.bobistheoilguy.com

 

What is all that crap? I tried to read through most of it, but it all was completely irrelevant to what we are talking about here.

 

I'd have to agree, while it is very good information, I don't see an answer.

 

Hopefully tunes12, you will find an awnser to your question as I would like to know as well (although not in attempt to create 40 weight oil by mixing 30 and 50 weight.)

Back to your original post, you were looking for something between 30 and 50 weight (40 weight) correct?
Mobil does make a synthetic 0w40 that I will be using. Someone posted some numbers of Mobil 1 5w30 vs. M1 0w40 and the 0w40 created about 10 psi higher oil pressure! Very good news for track events, etc..

 

Never taken my car to the track. Just another option.
Castrol makes a full synthetic thats 5w-50
Ive been running it in my car now for about 4 oil changes and have been pleased with how clean it stays and the performance it gives me. I use hamp oil filters. The temp where im at goes down to 30 in the winter and 100+ during the summer.