my first oil analysis on my Titan...

[jsharp]

quote:

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Originally posted by Last_Z:

quote:

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Originally posted by KJA426:
Many of the manufacturers are going to 5w-20 and Nascar engines run ghastly thin oils in qualifying. That leads me to believe the theory that thicker weight oils rob horsepower and fuel economy.

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What number of manufactures? Honda and Ford? That isn't very big!
I think everybody would agree with me that Toyota is the most reliable name brand out there. Why haven't they gone to XW-20 weights?

You cannot compare NASCAR and a street vehicle. They have million$ in annual budget$; their qualifying engine is used for qualifying only.....which is only a few laps; and when you talk about 700-750HP and much more importantly, 9-9500RPMs, then oil does become very critical!
Does your Chevette rev all the way to 9k RPMs?

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Actually, they have to use the same engine for the race now or their qualifying times get thrown out and they go to the back of the field.

But they've obviously spent plenty to make sure the engines will survive on the 30 weight oils they use. I'm with you on not comparing racing engines to those in out street cars. Not even close to the same situation...

 

[ekpolk]

quote:

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Originally posted by jsharp:
{snip}
But they've obviously spent plenty to make sure the engines will survive on the 30 weight oils they use. I'm with you on not comparing racing engines to those in out street cars. Not even close to the same situation...

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I would certainly agree that road and track are very different situations. OTOH, while the laws of the road may not apply on the track, the laws of physics and fluid dynamics certainly do. There was a very well established reason why ridiculously thin oils were used for qualifying. Does that support the position of the CAFE-meisters or "prove" that we should all use 10w oil to save gas and improve performance? Good grief no. But it does speak to the general point we've been discussing here.

 

[drm7]

Bror, I just sold my Mazda B4000 with the 4.0l V6. It's been said that these engines are harder on oil and that is why they still spec 5w30. I have no proof of this though. They do have 2 timing chains, one on front of the engine and one on the back. Each operates one bank of cylinders. I had never heard of this type of design before. These may shear oil faster and be the reason why 5w30 is still spec'd. I'm not a thicker-is-better guy but this kind of makes you wonder if some engines still spec 5w30 then why not run this in 5w20 engines? I also have a Mazda MPV with the Duratec based 3.0l V6 and it specs 5w20 but Mazda released a TSB allowing for the use of 5w30. Don't know why they did this though.

 

[jsharp]

quote:

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Originally posted by ekpolk:

quote:

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Originally posted by jsharp:
{snip}
But they've obviously spent plenty to make sure the engines will survive on the 30 weight oils they use. I'm with you on not comparing racing engines to those in out street cars. Not even close to the same situation...

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I would certainly agree that road and track are very different situations. OTOH, while the laws of the road may not apply on the track, the laws of physics and fluid dynamics certainly do. There was a very well established reason why ridiculously thin oils were used for qualifying. Does that support the position of the CAFE-meisters or "prove" that we should all use 10w oil to save gas and improve performance? Good grief no. But it does speak to the general point we've been discussing here.

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Of course. I'm not sure you and I dissagree on this. I don't think thinner is always better anymore than I think thicker is always the best choice.

In the case of Nascar engines though they're built and optimized to use the oils they use and to give the required life with those oils. That's all...

 

[MNgopher]

quote:

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Originally posted by Last_Z:
Where is the proof that thicker oils waste energy or decrease horsepower? In fact, we have had numerous people on here state the difference between thick and thin oils is minimal, if any when it comes to MPGs and HP.
Where is the data?

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Well, I recoggnize I can only provide one data point, but if you want real world results, I've run this exact type of comparison.

My '99 F150 4x4 Supercab Flareside with the 4.6l V8 called for 5w30 from the factory. Ford later back recommended 5w20 in this application. From the inception of the 4.6 (modular) series of motors, 10w30 was the tickest recommended from the factory, with some special cases (The Cobra R with a 5.4 specified M1 15w50) getting a thicker recommendaation.

Out of curiosity, I have now run 5w30 with UOA's for a year, 5w20 with UOA's for a year, and I am in the midst of running a 5w40 for a full year. I also keep meticulous gas records, separating out all sorts of details such as mileage vs. temp, versus brand, versus ethanol or non ethanol or unknown, etc...

Based on my first UOA of the Rotella T syn 5w40 over similar period (mileage, temps, driving style, etc...), I netted a 7% fuel mileage drop using 5w40 versus 5w20 or 30. On top of that, the UOA results were not really any better than when using the thinner oils.

I am commited to seeing my test out through the year, but based on what I am seeing, getting similar UOA results but losing 7% of my fuel mileage seems to indicate to me that if you can have your cake and eat it too, why not do it?

As an aside, I also switched from 5w30 to 5w40 in my Jeep Cherokee with the 4.0 and noticed no drop in fuel mileage. So while not a universal truth, thinner oils seem to be a better fit with many newer engine designs, which the 4.0 AMC designed engine in the Cherokee is most definitely not!

 

[buster]

I think everyone misses the point on this issue. It's not thicker vs thinner but choosing the best viscosity that gives you the best wear, mpg and HP. Take Patman's Vette for instance. GC is giving him great wear, HP and MPG. I don't see the point in using anything thicker in his case. Some cars need a thicker oil, some don't. Get over it.

 

[Last_Z]

quote:

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Originally posted by ekpolk:

quote:

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Originally posted by jsharp:
{snip}
But they've obviously spent plenty to make sure the engines will survive on the 30 weight oils they use. I'm with you on not comparing racing engines to those in out street cars. Not even close to the same situation...

---

I would certainly agree that road and track are very different situations. OTOH, while the laws of the road may not apply on the track, the laws of physics and fluid dynamics certainly do. There was a very well established reason why ridiculously thin oils were used for qualifying. Does that support the position of the CAFE-meisters or "prove" that we should all use 10w oil to save gas and improve performance? Good grief no. But it does speak to the general point we've been discussing here.

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EK,

Once again, you cannot compare a 700-750 HP engine that revs to 9500RPMs with anything on the street.
Reason being is those engines spend their entire race above 5-6k RPMs, but your G35 does not. Your oil will see multiple, short-lived spikes to 6k RPMs, but that's it. At a constant 6-9RPMs, the drag created by the oil becomes very big. The theory isn't really a theory.....is a fact!
A good example is air resistance. Let's assume your G35 achives 30MPG at 50MPH. Now, up the speed to 70MPH and your G35 will consume 25MPG. Go any higher than that and you're gonna need inflight refueling. So, the critical factor here is the amount of air resistance.......the more the worse the MPGs get.
Same for a NASCAR engine......the higher the RPMs, the more the drag multiplies.

Now, do thinner oils save gas and energy? Yes! How much? In my opinion, in a street driven car, driven normally like most people here do, minimal.....sometimes none.

We have a member here who has kept immaculate gas records. His findings were that thicker oils had a very......very slight penalty on MPGs.......many times none.

As for CAFE.......I believe the idea of saving a percentage of fuel as a fleet of millions using thin oil is putting the consumer in a dangerous situation, especially when the individual consumer see almost no savings at all.
I personally prefer thick 30W to top end 40W. Any thinner than that scares me.

 

[Last_Z]

quote:

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Based on my first UOA of the Rotella T syn 5w40 over similar period (mileage, temps, driving style, etc...), I netted a 7% fuel mileage drop using 5w40 versus 5w20 or 30. On top of that, the UOA results were not really any better than when using the thinner oils.

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Well, it's a shame you used Rotella T-Syn. The XHVI stuff has been hyped a bit as being extraordinary. From all UOAs that I've seen of this oil, results are in the "ok" to "poor" range. It isn't very friction modified and I just believe it is an average oil. I think Delvac 1300 or Motorcraft HD are much better and I believe MPGs would also be a tad better.
Good test though!

 

[ekpolk]

quote:

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Originally posted by buster:
I think everyone misses the point on this issue. It's not thicker vs thinner but choosing the best viscosity that gives you the best wear, mpg and HP. Take Patman's Vette for instance. GC is giving him great wear, HP and MPG. I don't see the point in using anything thicker in his case. Some cars need a thicker oil, some don't. Get over it.

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Ah buster, you've posted over 5k times, in the vast majority of those that I've seen, I believe you've been correct. But not this time. Sure, there is a best choice for each engine/vehicle combo, some thicker, some thinner. The issue, however, is when thick or thin might be preferable, and how much of an advantage one has over the other. If you've become impatient with this discussion, I can understand that, others wear on me. I respectfully recommend you move to a thread that doesn't irritate you while we finish wallowing in this particular mudpuddle. This will have two benefits: 1) you won't be irritated with us, and 2) I won't have to fend off any further misguided admonitions to "get over it".

 

[ekpolk]

There, now that I've finished buster off, it's your turn Z! I have an odd feeling that although we appear to be in disagreement, we actually pretty much agree. You should consider law school. We lawyers are really good at continuing to argue, even when there's nothing left to argue about.

Anyway, when I think of "comparing" a race oil with a street oil, I'm not suggesting doing so on a one-to-one basis. But I do think that there's a predictable curve that connects the two sets of conditions, and that, so long as you properly account for the differences, you can indeed compare the two. For example on the issue of fuel saving by "thinner" oils, the relatively small difference seen in street use conditions is hugely magnified in race conditions, yet underlying both situations are the same set of scientific principles and rules.

Now, here's some food for thought. I lifted this from a current thread in the main Gas Engine Oil forum this evening. The topic is why some oils are now GF-4, but not SM (and why some will soon be SM, but not GF-4). Anyway, here it is:
"Jelly:

I inquired to our tech department about your question concerning the High Mileage oils. This is his exact quote.

"Pennzoil & Quaker State HM oils will carry API SM but will not be ILSAC GF-4. The viscosity of the product does not allow it to pass the fuel economy requirements."

 

[Last_Z]

ek,

That last quote......that's for fleets right?

Again, you are right. ILSAC ratings are real and so are the fuel savings. But they achieve that as an overall fleet of vehicles. The individual driver would also save fuel.....but how much? More importantly.....is it worth it?

 

[Motorbike]

quote:

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Originally posted by buster:
I think everyone misses the point on this issue. It's not thicker vs thinner but choosing the best viscosity that gives you the best wear, mpg and HP.

Some cars need a thicker oil, some don't. Get over it.

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There ya go

Some of the difference lays in the torque output down low when talking MPG differences among oils and engines . There is major difference between a Miata and a 454 Chevy if some did not already know .

This thick vs thin thing will be never ending until the posters understand how the engine works a bit better . Since thats not going to happen overnite here is a PDF file that speaks of the ACEA TU5JP and oxidation along with how it affects fuel mileage with different VI's @ 40c .

Page 53 I think


http://www.atc-europe.org/info_/public/atccopfeb03.pdf

The Elf Worldwide website goes into detail on vi @ 40c and how it effects economy and gives some percentages . It's worth a look .

Take care now ya'll here and when oil analysis starts giving fuel mileage factors ,,,, drop me a line

 

[1sttruck]

On thicker vs thinner, why are the 'European' oils typically thicker, especially on the more expensive marques ? They're offered by the same companies that we see in the US. Europeans pay a lot more than we do in the US for fuel. Could it be that thicker oils typically provide better protection, especially under high load conditions ?

 

[tenderloin]

is it worth it?

Worth it? Sure it is worth it. Better mpg, better performance, lower emissions and AS GOOD IF NOT BETTER PROTECTION.

You keep mentioning "fleet" like it some special word. In case you did not notice, we are all in the same "fleet", a far bigger fleet than any company or organization you might be referring too. We use the same resources, breath the same air and drink the same water. Our combined savings in our "fleet" would even be better if old hard liners (surprised you are no longer using straight 50W) would remember it is 2005.

Oh yeah. I am sure you still advocate the use of the M1 carbine, the P40 Warhawk and non laser guided weapons? No? Hmm You must like those modern technological advances

 

[1sttruck]

As others have asked, if 5w-20 is being promoted in the US solely for better protection with no compromise on wear protection, why do the OEMs often recommend a heavier oil in Europe, Asia, Australia, and perhaps the rest of the world ?

 

[supraturbo]

Nice report, but every Titan UOA out there is outstanding. I should have a GC 0w-30 report from my Titan soon. 40 weight is the highest recommended weight in the manual so warranty issue's could be a problem should an issue arrise. I'm guessing your oil pressure guage is probably pegged all the time, mine runs high with the german castol, can't imagine how much oil pressure there would be with 50wt. I see you burned 1.2qts in a 5k mile span, the make up oil more than cetainly made this report look better, my titan has never burned a drop in 13.5k miles, that would also concern me. Mobil 1 0w-40 or GC 0w-30 would probably be a better fit for you, also you can use it year round.

 

[Jelly]

quote:

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Originally posted by supraturbo:
Mobil 1 0w-40 or GC 0w-30 would probably be a better fit for you.

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Agree...but without the probably.

[ November 15, 2004, 02:09 PM: Message edited by: Jelly ]