Viscosity and Wear

[Dr. T]

And a 4L jug of synthetic oil of your choice for his/her 1st B-Day...

Congrats...

 

[pscholte]

'Kule/Patman,

Your T-shirt ideas are WAY better than my suggestion...

Dr T...it's gotta be import...nuthin' is too good for the little ones' first jug of synthetic!!!!

 

[Mark in NY]

Originally posted by cvl:
[QB] You guys should check out manufacturer's recommended viscosities for cars sold in the US Versus the exact same car sold overseas.
One such example is the new Civic Si in the States. Honda USA recommends 5w20.........For the EXACT same car sold in England........10w-40 oil.
________________________________________________
cvl - I saw the same contrast with my car - Ford Contour here in the US is the big seller Mondeo in Europe and Australia. The 2.5 V6 is a nice running alum block motor. Here of course 5-30 is all she wrote. The Euro Mobil site has a very interesting specs page for this car - it says the Ford spec is 5-30 yet a footnote says Mobil still recommends 10-40 !! in opposition to the OEM !

My experience over the years has been that a higher SAE grade oil will provide more wear protection than a thin oil. HOWEVER there are some constraints. A motor that does not see frequent WOT use, does not pull a trailer or push snow and is not expected to go much beyond 100k miles can exist happily on anything that does not sludge. Road racing, autocrossing, "spirited" street driving give you a reason to go with a X-40 rather than a 30 wt. The newest Mustang Cobra uses M1 15-50 as a factory fill. Highly loaded bearings are why. Never push down on the pedal to produce more than 125 BHP max and SAE 0-20 will work fine.

As far as the many, many discussions on pumpability, "too thick" etc. put it in perspective over the entire real world temp range that the oil must operate in. The Mobil-1 0-40 that I am currently using in some of my cars is 12.5 cP at 225 degrees F (while I am in summer traffic w/ the A/C on). Mobil drive clean 5-30 is 9 at this temp. This is too thin for my preferences. BUT put this into perspective - the almighty "5-30" Mobil Drive clean (which is a bit thin in grade compared to other brands) at 75 degrees F when I started the car this morning was 120 cP. In December when it is 32 deg. F the 5-30 will be 500 cP ! Realize that this is a logrithmic scale but somehow the resistance of using a -40 in place of a -30 because of the arguements over high temp visc differences escapes me.

Last thoughts from engine teardowns & rebuilds- boundry lubrication (moly etc)does not apply to bearings. If the oil presssure is lost under power(like the sweeping turn at Lime Rock) the bearings melt and go away in the blink of an eye. Closer to home for our use on the street
I do not see thousanths difference between old engines with good and poor oil maintenance. The difference I see is ten-thousanths. It is really a difference of metal surface quality (as the term is used in machine shops)- the scuff resistance the oil provides- that I see. 2 cylinders that mic up about the same can show visual differences that I attribute to oil protection. Take two motors with 125K miles, one a clanky oil burner, the other a fairly tight quiet running unit. The differences in specs will be measured in 10ths(thousands) not thousands of an inch. This is why "Million mile motor still in spec" ads are worhtless as a claim.
All-in-all my interest in browsing this forum is to learn more about the best products and practices for keeping engines tight for OVER 150K. With most engines these days, if your target is less than that the discussions here are mostly academic.
Interesting stuff tho- with engineering, Madison Av, EPA, legal departments all trying to tell us a somewhat varying story about what is best for us all.........

 

[tweeker43]

from the huge maxima spreadsheet i compiled this data. the weights are ranked by ppm per mile. ppm doesn't include potential wear items like moly, which is also an additive. not all of the cars in the data are nissan maximas.

Wear by oil weight: ppm miles ppm / mile makeup oil makeup/mile
10W40 219 68730 0.0032 8 0.1164
20W50 96 16440 0.0058 2 0.1217
15W40 294 39755 0.0074 5 0.1258
5W30 2358 278986 0.0085 10.25 0.0367
10W30 1441 137900 0.0104 9 0.0653
0W30 286 18000 0.0159 1.5 0.0833
5W20 641 26420 0.0243 0 0.0000

quote:

---

Originally posted by buster:
It seems that all of us still really have varying opinions on this subject. I'm just curious if most people subscribe to the idea that a thicker oil is better for engine wear? The Steve Bergin article makes you think otherwise. What is exactly is the relationship between viscosity and wear? I don't think we have the answer yet but Bob and others have pointed out that thinner oils with greater flow might be as good or better.

---

 

[Ray Garlington]

wow, the last 2 posts by Mark in NY & Tweaker43 are awesome.

question for Mark

quote:

---

Realize that this is a logrithmic scale but somehow the resistance of using a -40 in place of a -30 because of the arguements over high temp visc differences escapes me.

---

Sorry, couldn't keep up with you here. Could you explain your point a little more?

question for Tweaker43
For each oil grade did you add the respective ppms and mileages for each oil weight that was reported?

 

[Mark in NY]

Ray,

Being an engineering sort, I like to see much info on a subject. SAE grades alone did not explain to me what the motor is really undergoing at different temps. I asked for and received temp vs viscosity graphs from Mobil for both the dino and synthetic families. My last comments were based on these graphs. I wish there was a way to post them here. They add a very interesting perspective of the viscosity discussions (dare I say debate!?)on this and other forums. If anyone knows the way to post pdf files here let me know. They are detailed to the point of requiring a full 8.5X11 print to see detail. If you want, PM me with your email address and I will send you the 2 pdf files.

 

[tweeker43]

quote:

---

Originally posted by Ray Garlington:
Tweaker43,

It appears that on average, the Maxima likes the heavier grade oils better than the thinner grade oils.

Can you identify which of the oils on the spreadsheet are synthetics to see if synth only results would be different? Also, how old are the maximas that are represented here (any particular year)?

---

here is by brand, but not weight. again, sorry for the formatting. i hope this is easier to read than the last one. it is important to take mileage into account when looking at this list. one sample of 3004 miles isn't really a good test.

the maximas are 1989 to 2001, with a smattering of honda, ford, dodge, mazda, bmw, lexus, chrysler.

Wear by oil brand:
ppm
miles
ppm / mile
mi / ch
ppm / 1000 mi

Mobil 1 Drive Clean Blend
10
3004
0.0033
3004
3.3

BMW Synthetic
29
6000
0.0048
6000
4.8

Castrol GTX
150
28479
0.0053
4747
5.3

ULX-110
162
28800
0.0056
9600
5.6

Amsoil
2013
288840
0.0070
9628
7.0

Honda
22
3130
0.0070
3130
7.0

Valvoline SynPower
44
5780
0.0076
5780
7.6

Mobil 1 SuperSyn
66
8644
0.0076
4644
7.6

Motorcraft
25
3250
0.0077
3250
7.7

Redline
220
27567
0.0080
6892
8.0

Royal Purple
54
5500
0.0098
5500
9.8

Mobil 1 Tri-Synthetic
1231
118108
0.0104
4921
10.4

Castrol Syntec Blend
215
17600
0.0122
5867
12.2

Unknown Dino
44
3000
0.0147
3000
14.7

Valvoline DuraBlend
108
6000
0.0180
3000
18.0

Amsoil Series 2000
188
10000
0.0188
10000
18.8

Valvoline MaxLife
105
5200
0.0202
5200
20.2

Pennzoil PureBase
225
10659
0.0211
2132
21.1

Factory-fill Motorcraft
186
3400
0.0547
1700
54.7

Honda Factory-fill
238
3270
0.0728
3270
72.8

 

[pete643]

quote:

---

Originally posted by QuadDriver:
The autobahn (which simply means motorway, not high speed proving track) now has a 130kph speed limit for its entire length, and due to safety emissions concerns, is 100kph in populated areas - welcome to the 2000's.

there is a misconception that the average joe in europe drives a bimmer or mercedes or lambo,

---

No QuadDriver, you are wrong with the German speed limits. The recommended speed is 130km/h but the Autobahn is still wide open, with no actual speed limits away from cities. I was there recently, and if you don't believe me go to:

http://www.germany-tourism.de/e/2433.html

As for the types of cars Gemans drive, Mercedes and BMW vehicles are very common. It seems like most of the taxis are Mercedes Benz cars. These cars are main stream in Germany and not out of reach of the average Joe. Mercedes and BMW produce cars at many price points.

 

[Mark in NY]

reference to the secondary topic in this thread-

Isn't the discussion on Euro cars, oils, and speed limits centered far to much on Germany?
There are dozens of countires in -western- Europe alone.
Fiats, Vauxhauls, Citroens, Ford of Euro, etc etc etc comprise the field. All I see referenced is BMW, MB.

 

[QuadDriver]

quote:

---

Originally posted by Mark in NY:
reference to the secondary topic in this thread-

Isn't the discussion on Euro cars, oils, and speed limits centered far to much on Germany?
There are dozens of countires in -western- Europe alone.
Fiats, Vauxhauls, Citroens, Ford of Euro, etc etc etc comprise the field. All I see referenced is BMW, MB.

---

hehheh, I once complained about this and even went as far as posting the top 10 lists of vehicles sold in europe (which as a whole has about the same size new vehicle market as the USA). I dont think it was the answer anyone wanted to hear.

Back to the primary topic.....you are right about bearings, somewhere somehow I had a link to a good explanation of the hydrodynamic suspension in a bearing, incl pretty pictures....suffice to say, the softest iron crank will destroy the best lead surface bearing in a few revs if a touch occurs.

 

[Mark in NY]

tweaker43-

how many samples, and cars of Mobil drive clean oil were there in this database?

From this sample of data, this Mobil dino oil will allow cars to last 2 million miles.!

Of course there are many questions that beg to be asked- one is - do the guys who beat on their cars the most, the same guys who tend to spend more and tend to use the "best" oil?
I drive like a little old man and use 99 cent Acme cheapo oil. My wear numbers are better than my friend who uses 9 dollar synthetic because he races his car weekly.
More data leads to more questions, and so it goes.
It is indeed tough to pick the magic oil that will extend our engine life.

If only I devoted as much detail to my internal UOA - you know, HDL, LDL, but thats another board !

 

[MolaKule]

"Teardowns of many blown racing engines taught me that putting gobs of very expensive moly powder in an engine did nothing extra if you momentarily lost the all-important oil film."

Moly powders or any solid lubircant not already "built-in" to a bearing material won't do much good.

Now if the moly is completely in solution (not suspension), it coats on the molecular level and gets in between the clearances to uptake on parts. I do think boundary adds can make the difference between limping home and sitting by the side of the road not moving.


"Getting a suficient oil film between moving parts **and maintaining it at all times** by the proper combination of pump output pressure, oil viscosity, oil pathway modification, addition of Accusump type auxilary oil supplies, etc, makes your motor last and last...."

Couldn't agree more. Hydrodynamic lubrication is in force about 97% of the time. Some time ago, a physicist proved that the ring/liner interface of the piston/cylinder was hydrodynamically lubricated through most of it operation.

 

[Ray Garlington]

Here is another view of Tweaker43's data. I categorized the oils by type (syn, dino ..) and calculated an average ppm/mile for each type. (May have made an error assigning oils to category, so check that.)

So, when you look by type, you see the expected (less wear for syn, then blend, then dino, and distant last factory fill.)

When you look at the same data by weight (regardless of type) you see the heavier oils 10w40 20w50 beating the lighter oils 5w20 10w30. It would be nice to see if there is enough data to breakout lightweight syn.

10W40 219 68730 0.0032
20W50 96 16440 0.0058
15W40 294 39755 0.0074
5W30 2358 278986 0.0085
10W30 1441 137900 0.0104
0W30 286 18000 0.0159
5W20 641 26420 0.0243

 

[moribundman]

quote:

---

reference to the secondary topic in this thread-

Isn't the discussion on Euro cars, oils, and speed limits centered far to much on Germany?
There are dozens of countires in -western- Europe alone.
Fiats, Vauxhauls, Citroens, Ford of Euro, etc etc etc comprise the field. All I see referenced is BMW, MB.

---

Mark in NY,

I think we restricted the (deviation in) discussion on German cars (as far as European makes went), because they got a good reputation, because they are popular for import/export in large parts of the Western world (Especially BMW, Mercedes, Porsche, VW/Audi), and because otherwise the discussion would probably never end.

As far as my participation in this discussion goes, I focus on Germany, because that's what I am completely familiar with. And don't forget, Europe is small and many other Europeans use the German Autobahn. Since Germany still has an interest in producing cars that are Autobahn-capable, you can pretty much trust that they will build motors that won't grenade after 2 hours of redlining.

PS: Regarding some other European car makers:
The Fiat company is almost bankrupt. Vauxhaul=Opel (GM-owned), Citroen=Peugeot (in cahoots with Nissan , IIRC), Ford is losing a lot of business in the EU. BMW owns Rover (and Morris?). Is Leyland still buliding cars?
What about Lada? Are those still just Fiat cars built under license? What about Russian cars? Moskvitch, anyone? There's just no way to talk about all of them.

 

[Eiron]

quote:

---

Originally posted by moribundman:
There's just no way to talk about all of them.

---

Ooh! Ooh! Let's talk about Trabants!

P.S.,
Since the topic here is (was?) viscosity-related, I'd just like to go on record as admitting that every time I see the banner ad for IgnoreYourHealthAndItWillGoAway.com (& you thought BobIsTheOilGuy.com was long!) I think it says, "Join Our Oil Weight Support Groups."

Every stinkin' time!!

OK, thanks for listening. I feel much better now ...

 

[Jay]

quote:

---

Originally posted by Mark in NY:
...This is why I continue to harp on viscosity here. It is the one variable that is easily adjusted on our street cars that can make a difference in engine life...

---

I don't see any evidence in the UOA section to support this contention. If I've missed a UOA that will back this up please post the link. I realize that good back-to-back comparisons of one viscosity to another are scarce as hen's teeth but I've found a couple of good ones between M1 0w-40 and M1 Xw-30 that show that the 30-weight protected as well as or better than the 40-weight.

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=000315#000001

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=000636

These aren't the definitive answer but some evidence is better than none.

As far as the Maxima spreadsheet data is concerned, I don't think it's useful because you're not comparing apples to apples. If you look at the individual UOAs you'll find a wide range of exceptions (like 30-weight user "A" uses a K&N air filter, user "B" had a coolant leak, etc.) that make the data useless for the type of comparison shown.

 

[Ray Garlington]

Jay wrote

quote:

---

As far as the Maxima spreadsheet data is concerned, I don't think it's useful because you're not comparing apples to apples. If you look at the individual UOAs you'll find a wide range of exceptions (like 30-weight user "A" uses a K&N air filter, user "B" had a coolant leak, etc.) that make the data useless for the type of comparison shown.

---

Jay,
There are half a million miles of UOAs represented there. A few problem children 'average out'. This kind of data is much better than one or 2 examples. Someone should start assembling 'our' UOAs into a database of some sort.

 

[Jimbo]

quote:

---

Originally posted by Mark in NY:
reference to the secondary topic in this thread-

Isn't the discussion on Euro cars, oils, and speed limits centered far to much on Germany?
There are dozens of countires in -western- Europe alone.
Fiats, Vauxhauls, Citroens, Ford of Euro, etc etc etc comprise the field. All I see referenced is BMW, MB.

---

Except for a few Jaguars, Saabs and Volvos, how many European cars are sold in North America are not German? Mexican-made VW's can also be counted as German-branded at least. Most members of this board are located in the USA/Canada.

I own a BMW, as lots of Americans do. I used to have a Ford Fiesta and have been to Italy and experienced the Fiat Uno. IMO, those cars were junk, not suitable for North America outside of, maybe, Mexico City. I hope that helps to explain the greater interest in Audi, BMW and MB.

 

[moribundman]

quote:

---

Originally posted by moribundman:
There's just no way to talk about all of them.

Ooh! Ooh! Let's talk about Trabants!

---

Eiron, I KNEW someone goes going to drag a Trabbi (East German celluloid bomber) out in the limelight. What's that got - a 2-stroke engine? They haven't been made in years, BTW.

Jimbo, Jaguar is now more Ford, Saabs are GM, and who knows what a Volvo is anymore.

[ July 16, 2003, 06:06 PM: Message edited by: moribundman ]

 

[Cary]

I just wanted to post some random notes concerning oil viscosity. Mark from NY was kind enought to send me the oil PDF's from Mobil, from which I took Mobil 1 graphs and overlayed a couple of the Mobil clean drive oils (Synthetic v. Mineral). It is interesting when you look at the graphs (Vertical Axis Centistokes in a logrithmic scale, horizontal tempurature also logrithmic) because they are linear. Here is where it gets real intersting:

1) The mineral 10w30 runs close in thickness to the M1 10w30. This is much different than the 20w-50 mineral v. 15w-50 M1 where the M1 15w-50 is far superior in pumpability at low tempuratures.

2) The M1 0w30 and 5w30 are so close through their tempurature spectrum that their lines run together. They are pratically the same oil.

3) M1 0w-40 has a flatter slope than any of the other oils, meaning that it changes thickness the least.

4) To give a few ideas about the thickness as various points:

For the oils to be 10,000 cst in thickness the tempurature of the oils is as follows:
M1 0w30 & 5w30 -33F
M1 0W-40 -30F
M1 10w30 -26F
Mobil Mineral 10w30 -18F
M1 15w-50 -15F
Mobil Mineral 20w-50 7F


For the oils to be 3000 cst in thickness the tempurature of the oils is as follows:
M1 0w30 & 5w30 -12F
M1 10w30 & 0w-40 -7F
Mobil Mineral 10w30 0F
M1 15w-50 8F
Mobil Mineral 20w-50 24F

For the oils to be 500 cst in thickness the tempurature of the oils is as follows:
M1 0w30 & 5w30 27F
M1 0W-40 40F
M1 10w30 32F
Mobil Mineral 10w30 38F
M1 15w-50 54F
Mobil Mineral 20w-50 67F

And finally for the oils to be 15 cst in thickness the tempurature of the oils is as follows:
M1 0w30 & 5w30 175F
M1 0W-40 207F
M1 10w30 182F
Mobil Mineral 10w30 183F
M1 15w-50 230F
Mobil Mineral 20w-50 228F


Take what you will from these numbers, but my view is 1) if you live in cold climate use the M1 0w-30, 5w30, or 0w-40, 2)Synthetic 15w-50 offers no cold start advantage over mineral 10w30, but does offer a significant benefit over mineral 20w-50, 3) As you get to operating tempurature (212F) all the 30 weights are the same, the 40 weight is thicker and the the 50 still thicker. Obviously in an extreme situation the Synthetics will withstand higher temperatures than the mineral oils before breaking down.

For me, I am now using Mobil 0w-40 in all my cars, a 94 BMW 525i, a 91 nissan Pathfinder, and a 96 Toyota landcruiser. I like the idea of the better oil flow at lower tempuratures, but still feel the 30 weight is to thin on the high end.

Interestingly, my Landcruiser and Pathfinder both call for 10w30 in warm weather, but overseas they spec 20w-50 for warm weather. The 40 weight gives me a better feeling.