Looking for thinner oil: 5w30 vs 0w30?

[4DSC]

Hi, after several days of lurking and searching I've just registered and this is my first post.

I'm blown away by the level of expertise here and how seriously you folks take your oil. Not that I'm new to that sort of feeling...

It's time for an oil change again, and I am looking for a synthetic that is the thinnest and runniest at startup as I can get away with. My car is a '92 Maxima with some notoriously fragile variable valve timing hardware in the upper end. I bought the car used a couple years ago and it was in good health since the previous owner had changed the oil on a regular basis. The owner's manual specifies 5w30 for this model and people have theorized that getting clean oil up there ASAP is the best way to keep the things alive. So last year I went and changed the oil to Mobil 1 5w30 TriSynthetic. Soon aftwards I found out about 0 weight oils and because of the "0" designation I thought that it would be thinner when cold, and thus better for startups.

Reading a lot of the threads and posts here I found out about the "German" Castrol Syntec 0w30 and, thanks to Patman's info, bought some at a Wal-Mart. My problem is that afterwards I seemed to read info that suggested that maybe this 0w30 oil was actually heavier than M1 5w30 at average room temperatures. It seemed that kinematic viscostity numbers correlated to this property. Is this a fair statement?

I did a some research and this is a cut & paste from what I compiled:

Kinematic Viscosity @ 40*C (cst) Comaprison:

M1 0w40....................80.3
M1 0w30....................54.8
M1 5w30....................53.7
M1 10w30...................61.3
M1 15w30..................124.7

M1 Delvac1 5w40............95.0

Castrol Syntec 0w30........68.5

REGULAR OILS FOR COMPARISON
Esso 5w20..................47
Esso 5w30..................66
Esso 10w30.................71
Valvoline 5w30.............63
Valvoline 10w30............71
Pennzoil 5w30..............60
Pennzoil 10w30.............67
Quaker State 5w20..........45(!)
Quaker State 5w30..........64
Quaker State 10w30.........69
(sorry about the weird formatting - can't get it even!)

It looks like the Delvac1 that I thought might be "better" was too thick, and the Made in Germany Syntec 0w30 is actually closer in viscosity (when "cold") to a conventional 10w30. Is this right?

I also remember reading about how people commented on how thin the M1 5w30 seems compared to other oils, and the numbers above seem to support that. It's kind of funny that "0" weight oils scare people away because they sound too thin, since that's exactly what I'm trying to find (unless my reasoning on this is totally wrong

).

I've tried searching a lot about this issue, but couldn't really find a good answer to help my confusion on this. I currently have a jug of M1 SuperSyn 5w30 and 4 bottles of Syntec 0w30 sitting in the basement and I just need to know which one to return.

Thanks and sorry for the long post!

Brian

 

[buster]

I'd run Mobil 1 because A. it is thin and B. it will protect very well. I wouldnt settle for a brand of lesser quality bc it is thinner.

 

[rugerman1]

4DSC

That is THE most impressive first post I've ever seen!
Keep in mind that base oil type/viscosity is only one factor in choosing an oil.IMHO,The additive package is more important than the juice it's in.

Mark

 

[MolaKule]

Now you know why I stick with the 10W30's.

Once the base oil has carried the additives to the top end, one should't have to worry too much about subsequent starts.

Look for an oil with a good additive package that contains AW's and FM's like Boron, Moly, and ZDDP in quantities above 50 ppm.

Check the VOA and UOA sections.

 

[nicrfe1370]

If you haven't already, check out the maxima.org forums, there is a contingent of folks there who have experimented a lot with oils, and have the single most impressive spreadsheet of their results to back it up.
Also, consider an ester based oil, namely Red Line. One of the major pro's of esters is their insane low temp tolerance. I hear that Red Line is absurdly expensive in Canada, so that may not be an option.
Unless the 0W-30 German Syntec is a major turning point in Castrol's North American offering(which we won't know until there are a bunch of UOA's), I would go with the Mobil 1.

[ June 05, 2003, 05:59 PM: Message edited by: nicrfe1370 ]

 

[Al]

I would return the Syntec. There is very little difference between the 0W, 5W, and 10W Mobil 1. Really doesn't matter which one you choose. I prefer the 10W-30 all year round. As far as is it better to have better flow or better viscosity on startip. I really don't think it is an issue above 60 degrees or so even with a 10W conventional oil. With any of the mobil 1 oils I don't think it is ever an issue. Good to see you are doing your homework.

As you see 10W Mobil 1 is as good as many 5W conventional oils. And the colder it gets-the better.

As you probably have read Syntech is not a "true" synthetic oil.

 

[Dr. T]

Brian, although "thinner and runnier at startup" is a fair goal to look at achieving, looking at the vicosity at 40 Celcius isn't the number you should be looking at.

Remember, this is the temp. during the hottest of times in Phoenix, AZ! Yet, the running temp. of the engine is much higher....therefore, it is nothing more than a 'transient' number within the viscosity range.

The number to look at is the cold cranking simulator specs (CCS) for the oil in question. Now, because these are standardized by the API, all grades containing the same first number of the grade will be about the same viscosity at the required temp. eg. all 5 weight oils (eg. 5-30 or 5-40) will be the same viscosity when "cold" ie. at -30C.

As the oil temp. goes up you will get a gradual thinning (as with all fluids)...and here's where you'll see the crossover above. The final comparison figure is the cSt at 100 C because here is where you will note that oils with a higher second number will thin less. This assigned number range is also standardized by the API.

As such, you will notice a crossover at 40 C of the varying grades. ie. a 0 grade will start out thinner at extreme cold, but all 30 grades will be about the same thickness at 100C (determined by API).

As far as your goal, (thinnest at startup), all oils will flow like water (figuratively speaking) when hot...this includes 40C...so the only concerns come at extreme cold....and even 15 weight are certified down to -20C...with 10 weights certified down to -25C and 5 down to -30C...0 down to -35C.... at 40C, the number is pretty much inconsequential...(whew...I need a drink

)

 

[Patman]

quote:

---

Originally posted by Al:
I would return the Syntec. There is very little difference between the 0W, 5W, and 10W Mobil 1. Really doesn't matter which one you choose. I prefer the 10W-30 all year round. As far as is it better to have better flow or better viscosity on startip. I really don't think it is an issue above 60 degrees or so even with a 10W conventional oil. With any of the mobil 1 oils I don't think it is ever an issue. Good to see you are doing your homework.

As you see 10W Mobil 1 is as good as many 5W conventional oils. And the colder it gets-the better.

As you probably have read Syntech is not a "true" synthetic oil.

---

Al, he's talking about the 0w30 German made Syntec though, which is definitely without a doubt a full synthetic. No group 3 oil is going to get a pour point like it has.

I really wish oil companies would give viscosities at a few other data points other than just 40 and 100c. It would be nice to see them list their viscosities at 0c and 20c too. It is kind of odd that many of the 0w30 and 0w40 oils out there actually end up having a thicker viscosity at 40c than most 10w30 oils, but yet at the same time they can flow so much better in the extreme cold.

 

[buster]

quote:

---

I really wish oil companies would give viscosities at a few other data points other than just 40 and 100c. It would be nice to see them list their viscosities at 0c and 20c too

---

Definitely.

 

[userfriendly]

Patman; I was just about to say exactly that, but you beat me to it. I think the essence of your post is the many different opinions people have of what a multigrade lubricant really is and how the specification sheet does not tell much of the story. Here is my opinion and remember that this is only my third post so I am just learning. I read somewhere that the "W" number was originally given to engine oils that were intended for, or should I say suitable for winter use giving particular attention to cold flow numbers expressed in the old days as viscosity in saybolt seconds taken across the board at zero degrees F or -18C. I think the article said that a multi grade oil is an oil that meets more than one SAE grade. I suppose that at one time or originally the -18C viscosity rating was the determining factor in giving winter oils their various "W" numbers. As we know, those -18C viscosity umbers are no longer posted in spec (typicals) sheets because the format for determing the performance for the various winter grades have changed to a more temperature specific performance rating. I think that maybe a better way of viewing say a 5W40 multi-grade engine oil is that it is an SAE 40 oil that meets the flow and cranking performance at the temperatures set out for a 5W oil. The other way and the one people hold dear to in veiwing a 5W40 engine oil is it is a 5W oil that does not thin out as much as a straight grade oil might and holds enough viscosity at 100C (212F) to qualify that oil as an SAE 40 as well. I would say that since the parimiters set out for a 5W engine oil only specifies a minimum hot viscosity and the maximum is open-ended, perhaps that second example or way of thinking is correct. I don't know why oil companies publish the 40C viscosity as it is really quite meaninless and is the temperature that the ISO rates their industrial fluids and lubricants that quite often operate in or around a 40C, or maybe they just had to pick a number between one and one hundred and 40 sounded reasonable being close to 100F. My opinion, and it is just that and everyone one of those too, in the application that started this thread I would not worry about cold start-up protection in Vancouver BC Canada especially at this time of year when hot performance and protection provided by an XXW40 may be more important. I surly wouldn't consider the room temperature values given on a spec sheet much weight either in any case.

 

[YZF150]

4DSC, use the German oil. Watch for analysis on it soon from Patman, and do an analysis yourself.

Patman, hurry up.

 

[YZF150]

userfriendly, well said.

Feedback on post: shorten the paragraphs. Hard to read in one huge chunk.

 

[4DSC]

Thanks for the replies and welcomes everyone.

I went and did some MORE searching around and reading and I feel a little closer to an answer, but the more I read the more it seems that no one else definitively knows the answer either!

quote:

---

Originally posted by Dr. T:
Remember, this is the temp. during the hottest of times in Phoenix, AZ! Yet, the running temp. of the engine is much higher....therefore, it is nothing more than a 'transient' number within the viscosity range.

---

Thanks Dr.T, interesting stuff and I found out about the SAE J300 spec. Since the xW grade is determined by a cold cranking/pumping range at a very low temp though, is it really useful at looking viscosities at room temperature?

I had to actually rough sketch out the relative viscosities at different temperatures to wrap my brain around the concept of crossover and how a 0w30 is (ever so slightly) thicker at higher temps yet thinner at the extreme lows!

I reached the conclusion that this meant that 0w30 becomes thinner at "some point between +40 and -30-ish"

which isn't too helpful since no one can really say what temperature that occurs at.

Still, isn't 40C closer to around 20C than the low temperatures that are used to measure CCS? For what I'm wondering about, neither cold cranking/pumping or 100C cSt (basically all the numbers in the 0w30 or 5w30 designation) don't seem to matter...?

I would like to actually try the Syntec 0w30 since it seems to have impressive credentials, but for now the 40C viscosity number is still turning me off...

I guess this is all boiling down to the simple question: Are 0w30s thinner or thicker than 5w30s at room temperatures? (All other things being equal.)

Excuse me while I empty my brain now!

 

[userfriendly]

4DSC; You are much too hard on yourself. I think you might be trying to come to a conclusion without enough evidence or information. Maybe step back form those room temperature figures for a minute and look at the viscosity numbers that really matter which are:
In winter and low ambient temperatures, the xxW rating of the oil or its winter grade.
In summer and at the operating temperature of the engine the SAE grade, which is the second number such as 10WXX. The XX being 30, 40 ect, and the flash point of the oil.
4DSC, Don't try and learn this stuff over night. It is hard to be self educated without any face to face discussion with anyone, especially when it comes to topics about lubricants.
I read through some of the threads and added a few of my assumptions and theories of my own.
Read through these threads and let the experts on this site answer your questions, (and take everything I say with a pound of salt).
"Rethinking the synthetic/VI improver issue"
"Help! Can someone please explain the difference between straight and multi vis oils?"
Someone once said that I should read more and write less. Well by looking at the post time, you can see I do a lot of both.

 

[Patman]

quote:

---

Originally posted by YZF150:
4DSC, use the German oil. Watch for analysis on it soon from Patman, and do an analysis yourself.

Patman, hurry up.

---

I was all set to drain and sample my sister's oil this week! She was supposed to come over and visit before her trip, she wanted to see my son since she hasn't seen him in 2 or 3 weeks and he's growing so fast! (19 months old now) But she got caught up with working too much before her trip and never came over, so now I'll have to wait until June 18 at the very earliest before I can drain her oil.

 

[Mark in NY]

Brian,

Busters first reply really hits it on the head.

I would suggest however that for purposes of comparison if you want to continue your investigation that you get the actual temp vs viscosity charts from the petro manufacturers.

It really is a case of a picture being worth a thousand words. You can see what the viscosity value is at your real world startup temp of say 45 degrees F. - something the 40/100C numbers just dont show.

I got 2 charts from the helpful tech guys at Mobil. One for M1 and one for their pertoleum line of multi vis oils.

It is very interesting of write in the M1 0-40 line on the dino oil chart - this is just the info you are looking for.

If you have trouble getting the charts, PM me and I will email them to you.

Maybe we should pester all of our favorite manufacturers to supply this info on their web sites?!

BTW, the lines for 0-30, 5-30, 10-30 on the Mobil1 chart are just about overlapping for the entire temp range.
0-30 is actually a bit thicker at 100C - I think this is improved technology showing through on this one which is their latest oil (other than 0-40)

Mark

 

[Schmoe]

Sooooo, let me decipher some of this. The 5W-20's are really thin. I wonder is that why the manufacturers are using this oil because it will get oil up to the valve train faster, as in 4DSC's concerns? We here a lot about engine tolerances are tighter now. With that being said, it does make sense that a thinner oil, when NOT WARM, will "shoot up" there quicker????
Second, in userfriendly's post, sounds like this time of year we could use a straight weight and get the same benefits without the reliance on VI's. Is that what I'm reading? I asked this on a former post a little while ago and the majority of the brethren said pretty much no. I am one of those that have been grilled in the head that the W is strictly cold flow.

 

[userfriendly]

Shmoe; You have been reading through the threads a lot longer that I have. What reasons do the others give to support their opinions that a multi-grade engine should be used at all times, even in hot weather.
This should be fun.

 

[Chris Jefferson]

I definetely w/out a doubt would return the Mobil 1. Although you can use M1 0w-40 w/out ANY probs and youll prolly like it allot. My friend has a 02' Spec-V Sentra and also has VTC (his is CVTC just an evolution but nowhere liek NeoVVL. ie. think of hondas VTEC but WAY better. these make TORQUE!

and he uses the M1 0w-40 and LOVES it as I do!

However, I would still use the german 0w-30 as i have been using for almost 2,000 miles and i love it more than M1 0w-40 and my friend (w. the Spec-v) is also about to switch over to it. Of course, he first ran M1 15w-50 and loved it too but i convinced him that although he does have a larger displacement 4 cylinder (2.5 litres) he still should go no higher than an Xw-40 oil.

Off topic: has anyone seen the enw Mobil 1 5 quart jugs recently? They are really cooler looking and A LOT easy to handle/pour with. Almost looks like the 4 & 5 litre jugs of Castrol R 0w-40 i see advertised in my Formula 1 magazines.

 

[Chris Jefferson]

Oh, almost forgot why i originally posted. Do not concern yourself so much with the viscosity of an oil at 40C too much 'cause, so long as you use a 0w-XX or a 5w-XX viscosity oil youll be fine. Esp. in winter. A 0w-XX oil will most likely flow the quickest to the VCT area your worried about but once your past the cold start point itll be lubed up just fine.

Remember, 40C is hot for us, but not for internal engine temps, esp. combustion temps and in or around the pistons (your engine has oil jets to cool the piston skirts like the SR20DE(T) motors did right?

BTW, youve got a JEWEL of an engine as it was originally conceived for DTM or at teh time I think its was just called German Touring cars champ. and the series called for production spec motors to be used and then they changed the rules and the VQ30DE (or is it VG30DE? think thats the 300ZX engine)was ruled obsolete. Goodie for us though!!!