Looking for factual technical info re 5W30 use in TDIs

pleopard

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I realize this has been discussed; however, I'd like to approach it from a slightly different angle. Historically, car and truck diesel engines primarily ran either 15W40 or synthetic 5W40 oil. So, what has changed in modern diesels that now allows the conversion over to strictly 30 weight oils? _Or_, perhaps a better question is, have oils advanced enough that modern 5W30 oils can perform as well or better than 5W40, at least in modern engines? What are the technical reasons for running only 40 weights in the past? I find it much more difficult now to source 505.01 oil that's 5W40. As such, I'm simply running 5W30 (Total Ineo MC3 505.01).

Secondly, is there any hard evidence that a 30 weight oil is not as effective at lubricating a modern diesel engine in a car? If there is any hard evidence, then I find it difficult to believe that VW would allow such oils to carry 505.01 certification. I honestly do have more faith in VW than most people here. The 505.01/507 specs obviously can't be purely for fuel economy and emissions, though I wouldn't be too surprised if they were heavily biased towards fuel economy/emissions. Any technical documents that support using 40 weight oils over 30 weight oils would be appreciated.

Finally, just out of curiousity, are there any 5W40 oils that are 507 approved?

Oils I can probably get are Motul or Fuchs 5W40 with 505.01 certification, but it will be a lot less convenient to get these oils.

Thanks for the thoughts in advance.
 

Drivbiwire

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5w30 is typically used to squeeze out a few more MPG's. In respect to engine wear yes an engine running a 5w30 will wear faster than an engine running a 5w40.

"When it comes to protecting an engine remember two things: Viscosity and Viscosity! (G.M. STLE RIP)"

If you are running a 2009 in my opinion run an MB approved 229.51 oil. This meets the requirements of the DPF and NOx treatment systems. MB229.51 = VW507.00 (or really darn close to it). In some cases you could even apply the MB228.31 which is the Heavy duty specification oil for big diesels that have DPF and NOx treatment systems. These have a little higher Sulfated Ash but also come with higher TBN's for long drain service intervals.

MB is pushing the 5w40's rather than 5w30. Fact, MB forbids the use of a 5w30 anytime the temperatures are above 80F in ALL their vehicles! In the AMG series 5w30 if forbidden regardless of temperature! From a design standpoint the MB is very similar to the VW except for the two additional cylinders and V6 configuration. Dual overhead cam, 4 valves, rockers etc. The emissions sytems are also similar except for the Adblue on the MB. VW since the cars are much smaller can get away with the non-Adblue catalysts. Either however is extremely sensitive to sulfur (requires an optimal 10ppm sulfure fuel) in addition to Low SAPS oils (VW507.00, MB228.31 and MB229.51).
 
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hid3

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Oil with much miles on it gets thicker. 506.01 & 507.00 are long-life oils designed to be run up to 30,000 miles (thirty thousand miles) betwwen changes. That's why they're Xw30. And NO there aren't and won't be any 5w40 oils meeting 507.00

Motul and Fuchs are really good oils. Fuchs was the first company who was asked by VW to make a special oil (505.01) for PD engines. I believe Fuchs is (was) the factory fill for every engine VW made.
 
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pleopard

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Thanks guys. I wonder why then, companies such as Ford and Honda are recommending mostly 5W20 oils if lubrication is sacrificed. It would be interesting to see just how much fuel economy increases (I'm assuming fairly little) and engine longevity decreases with 5W30 and 5W20.

Drivbiwire, thanks for the great reply. I still just find it very difficult to see why car companies would sabbotage their own engines like this. Perhaps the increase in wear is extremely small? --- and no, I haven't done any own UOAs for my own application.
 

hid3

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I think it's worth to mention that let's say 5w40 oil is not exactly 5w40 and 5w30 might not be exactly 5w30. AFAIK VW (spec. meetin) oil viscosities are 'in range'. For example if you have a 5w40 oil then it might be 5w38 or 5w39 in reality. While 5w30 might be 5w32 or 5w33 one :) Well, you get the idea..
 

GoFaster

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pleopard,

The auto companies are not interested in you getting 400,000 km out of your engine. They are interested in you getting past the warranty period plus enough of a margin beyond that, that they don't get a bad reputation. A couple years ago I read that the average car in the scrap yard has something like 220,000 km on it. 'Course, that is not what most VW TDI owners are interested in. Heck, mine has more than that on it now.

The other thing is that a good many newer-design auto engines use roller-follower lifters at the camshaft (the 2009+ VW common-rail TDI is one of them), and yours uses flat-tappet lifters. This is a major factor as far as the lubricant properties are concerned. The main and rod bearings can handle lighter oil because those are a "surface contact" loading condition, but cam-followers are "line contact". "Line contact" implies infinite contact stress. In reality, of course, the load has to get spread out, and it's either gonna happen by the lubricant forming a wedge of finite dimensions (if the oil is thick enough - good) or by the follower or cam lobe locally deforming (if the oil isn't doing what's needed - bad).
 

pleopard

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GoFaster, thanks for that! That made a good amount of technical sense... I'll look into switching back to a 5W40 505.01 oil. If I ever get a CR TDI, maybe I'll feel a little better about running the 5W30 507 oils.
 

bluesmoker

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Drivbiwire said:
5w30 is typically used to squeeze out a few more MPG's. In respect to engine wear yes an engine running a 5w30 will wear faster than an engine running a 5w40.

"When it comes to protecting an engine remember two things: Viscosity and Viscosity! (G.M. STLE RIP)"

If you are running a 2009 in my opinion run an MB approved 229.51 oil. This meets the requirements of the DPF and NOx treatment systems. MB229.51 = VW507.00 (or really darn close to it). In some cases you could even apply the MB228.31 which is the Heavy duty specification oil for big diesels that have DPF and NOx treatment systems. These have a little higher Sulfated Ash but also come with higher TBN's for long drain service intervals.

MB is pushing the 5w40's rather than 5w30. Fact, MB forbids the use of a 5w30 anytime the temperatures are above 80F in ALL their vehicles! In the AMG series 5w30 if forbidden regardless of temperature! From a design standpoint the MB is very similar to the VW except for the two additional cylinders and V6 configuration. Dual overhead cam, 4 valves, rockers etc. The emissions sytems are also similar except for the Adblue on the MB. VW since the cars are much smaller can get away with the non-Adblue catalysts. Either however is extremely sensitive to sulfur (requires an optimal 10ppm sulfure fuel) in addition to Low SAPS oils (VW507.00, MB228.31 and MB229.51).
i respectfully disagree, viscosity is one component of engine wear, but from what i have read the single most important determinant for engine wear is the additve package, for example mobil 1 now produces an incredibly light 0-20 and claims almost no wear, even in 8000 rpm racing motors

https://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_Racing_0W-20.aspx
 

raybo

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Drivbiwire said:
If you are running a 2009 in my opinion run an MB approved 229.51 oil. This meets the requirements of the DPF and NOx treatment systems. MB229.51 = VW507.00 (or really darn close to it). In some cases you could even apply the MB228.31 which is the Heavy duty specification oil for big diesels that have DPF and NOx treatment systems. These have a little higher Sulfated Ash but also come with higher TBN's for long drain service intervals.

MB is pushing the 5w40's rather than 5w30. Fact, MB forbids the use of a 5w30 anytime the temperatures are above 80F in ALL their vehicles! In the AMG series 5w30 if forbidden regardless of temperature! From a design standpoint the MB is very similar to the VW except for the two additional cylinders and V6 configuration. Dual overhead cam, 4 valves, rockers etc. The emissions sytems are also similar except for the Adblue on the MB. VW since the cars are much smaller can get away with the non-Adblue catalysts. Either however is extremely sensitive to sulfur (requires an optimal 10ppm sulfure fuel) in addition to Low SAPS oils (VW507.00, MB228.31 and MB229.51).
DBW -

Does MB ban 5w30 oils that meet 229.51 (like ESP 5w30) where the ambient temp is above 80F? Check this out - scroll to the bottom:
http://www.whnet.com/4x4/oil.html

here it is cut from the link:
MB sheet 229.51 approved oils; low ash long life
Mercedes pioneered this new spec for passenger cars with diesel engines with exhaust particulate filters, and gasoline engines, and longer service life than the 229.31 oils. The spec was introduced in 2005. Change intervals increased to 20,000 kilometers. Based on ACEA A3 B4 and C3. As of December 2008 more than 100 oils meet this spec, including:
Aral SuperTronic 229.51 0W-40 LOW SAPS
Aral SuperTronic Diesel 229.51 0W-30 LOW SAPS
Bizol New Generation SAE 5W-30 (added 09 July 2007)
Castrol EDGE Formula RS SAE 0W-40 (added 09 July 2007)
Castrol EDGE Turbodiesel SAE 0W-30 (added 09 July 2007)
ELF Solaris LSX 5W-30
Fuchs TITAN GT1 229.51 SAE 5W-30
megol Motorenoel New Generation SAE 5W-30
Mobil 1 ESP Formula M 5W-40 (to become available in the USA on 15 May 2006)
Mobil 1 ESP Formula 5W-30 Emission System Protection (Europe, from December 2005)

Motul Mercedes-Benz Specific 229.51 5W-30 (added October 2008)
OMV BIXXOL special C3 SAE 5W-30 (added 09 July 2007)
Pentosynth HC 5W-40 (added December 2007)
Pennzoil Platinum European Ultra Diesel 5W-30
Pennzoil Platinum Low SAPS 5W-30
Q European Engine Ultra Diesel 5W-30
Quaker State Synquest Low SAPS 5W-30
Shell Helix Ultra AX 5W-30 Mercedes 229.51
Sunoco Synturo Xenon SAE 5W30 (added 09 July 2007)
Total Quartz INEO MC3 5W-30
Valvoline SynPower MST 5W-30 229.51 (added 01 June 2006)
Valvoline SynPower MST 5W-40 229.51 (added November 2007)


Ray
 
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pleopard

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i respectfully disagree, viscosity is one component of engine wear, but from what i have read the single most important determinant for engine wear is the additve package, for example mobil 1 now produces an incredibly light 0-20 and claims almost no wear, even in 8000 rpm racing motors

https://www.mobiloil.com/USA-English...ing_0W-20.aspx
"Are recommended for a wide range of race engine applications, including highly loaded flat tappet designs." Interesting.

So, now this begs another question - if lower viscosity oils can perform as well as higher viscosity oils at preventing wear, why run a higher viscosity oil? cheaper? So many questions, so many unknowns...
 

SBAtdijetta

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Yea but how often do they tear down that "race" motor... ;-). Don't think you want to be doing that with your DD.

Also I doubt an oil like that can go to more than a few thousand miles per OCI *IF even near that far.
 

TooSlick

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Regardless of whether they're a 30wt or 40wt, the VW 505.01 & VW 507.00 specs require a high temp, high shear (HT/HS), viscosity of at least 3.5 Centipoise (Cp) @ 150C. All these VW spec oils fall in the 3.5-3.8 Cp range - whether they're 5w-30 or 5w-40. The point is that there's little functional difference in their viscosities. The list below illustrates this point & includes the low viscosity VW 506.01, and high viscosity API spec oils for comparison:

Oil Spec----------HT/HS Viscosity range(150C)

0w-30------3.0-3.1 Cp
(VW 506.01)

5w-30-----------3.5-3.6 Cp
(505.01/507.00)

5w-40-----------3.7-3.8 Cp
(505.01/507.00)

API/5w-40------3.9-4.3 Cp


The only significantly thinner oils are the VW 506.01 spec oils; the only significantly thicker products are the API, CH-4+ or CJ-4 diesel oils....

TS
 

GoFaster

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pleopard said:
"Are recommended for a wide range of race engine applications, including highly loaded flat tappet designs." Interesting.

So, now this begs another question - if lower viscosity oils can perform as well as higher viscosity oils at preventing wear, why run a higher viscosity oil? cheaper? So many questions, so many unknowns...
Just because something is suitable for a racing application (where more than likely the engine will be inspected or rebuilt on a rather frequent basis and it will scarcely see idling or cold starts) doesn't mean it will be suitable for lasting for 400,000 km of cold starts, hot starts, idling, etc.!

Hydrodynamic lubrication is a funny thing ... The faster the surfaces move relative to each other, the less likely the oil will be squeezed out of the gap between the parts, and the higher load that the bearing can carry, *provided* you can get enough oil in there. So, a light oil that is successful at achieving hydrodynamic lubrication at high engine revs might not be successful in doing that at idle ...
 

bluesmoker

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GoFaster said:
Just because something is suitable for a racing application (where more than likely the engine will be inspected or rebuilt on a rather frequent basis and it will scarcely see idling or cold starts) doesn't mean it will be suitable for lasting for 400,000 km of cold starts, hot starts, idling, etc.!

Hydrodynamic lubrication is a funny thing ... The faster the surfaces move relative to each other, the less likely the oil will be squeezed out of the gap between the parts, and the higher load that the bearing can carry, *provided* you can get enough oil in there. So, a light oil that is successful at achieving hydrodynamic lubrication at high engine revs might not be successful in doing that at idle ...
i believe these "racing oils" have very high phosporus and zinc levels which allows them to have low viscosity but excellent metal to metal wear properties

You say the new Mobil 1 Racing oils are not for street use. Why is that? Does that mean I can't use these oils if my race car is also my daily driver?
Automotive street use oils that meet the latest industry standards are required to have a lower level of Zinc and Phosphorus anti-wear chemistries than oils formulated years ago. The latest automotive street use engine oils are designed to be compatible with emission control equipment. Mobil 1 Racing oils are formulated with anti-wear (Zinc/Phosphorus) chemistries at twice the level of automotive street oils to provide enhanced protection of highly loaded valve train systems found in some race engines. Based on the high level of anti-wear chemistries, Mobil 1 Racing oils are not recommended for street use.

http://www.mobil.com/USA-English/MotorOil/Files/Mobil_1_Product_Guide.pdf


not p and zn level for racing oils

this supports my arguement that the additives are more important than viscosity when related to engine wear
 

Drivbiwire

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raybo said:
DBW -

Does MB ban 5w30 oils that meet 229.51 (like ESP 5w30) where the ambient temp is above 80F? Check this out - scroll to the bottom:
http://www.whnet.com/4x4/oil.html
Here is what MB has to say about that:

MB approved viscosity operating ranges:

Oil specifications for these ranges include:
Engine 113 - MB229.5
Engine 156 - MB229.5 (only 0w40 or 5w40 may be used)
Engine 272 - MB229.5
Engine 273 - MB229.5
Engine 275 - MB229.5
Engine 642 - MB229.51 (Bluetec and CDI)

Cold climate oils:
86F/30C and below - 0w30,5w30 meeting appropriate MB specifications 229.XX

Hot climate oils -4F/-20C and above 86F/30C - 10w40, 10w50, 10w60 meeting appropriate MB specifications 229.XX

Hotter climate oils +5F/-15C and above 86F/30C - 15w40, 15w50 meeting appropriate MB specifications 229.XX

Hottest climate oils (Racing/AMG etc) +23F/-5C - 20w40, 20w50 meeting appropriate MB specifications 229.XX

Wide range oils:
Above 86F/30C and below -13F/-25C - 0w40, 5w40, 5w50 meeting appropriate MB specifications 229.XX

Narrow range oils:
Above -4F/-20C but not above 86F/30C - 10w30 meeting appropriate MB specifications 229.XX

ref. P18.00-2199-31

Speaking for myself, I can't run a Xw30 due to the temperature ranges of where I live. The temperature will hit 100+ in the daytime, drop to the 50's at night in the summer.

In Europe they live far enough north that the Xw30's serve them quite well year around. Seldom do they get above 86F except rarely in the summer, how many Europeans even have A/C on their houses much less their cars?

In the US very few regions permit the use of any Xw30, Anchorage AK may be one of the few places where you could safely run an Xw30 year around.

Why would you want to run an Xw30 when an Xw40 will provide better protection on the upper temperature ranges and still match the Xw30 on the cold climate ranges? One oil type year around with the same level of protection afforded by the narrower range oils, sounds like a no brainer to me!

When you start talking about wear rates with comparing and Xw30 to an Xw40 it's no contest as to what oil is superior!
 
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raybo

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DBW -

Have wear rates been shown to increase when ESP 5w30 was used vs ESP 5w40, or is this theoretical? I have no proof, but I think it would be hard to show much if any difference between the two formulations except under extreme conditions. In any case, aren't upper engine temps controlled by the thermostat? Why does ambient temp come into play except for cold starting?

Ray
 
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TooSlick

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The rate of heat transfer from the oil pan & block to the outside air is reduced as temps increase. So to some extent your equilibrium oil temps do track the air temps. The difference between Summer and Winter can be on the order of 10F-15F. (My Audi 100 had factory installed oil temp & oil pressure gauges, so I could study this effect).

The ESP 5w-30 & 5w-40 are very close in terms of HT/HS viscosity:

5w-30, 3.6 Cp
5w-40, 3.8 Cp
(a difference of ~ 5.5%)


I'd expect them to perform about the same...

TS
 

velociT

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Drivbiwire said:
Speaking for myself, I can't run a Xw30 due to the temperature ranges of where I live. The temperature will hit 100+ in the daytime, drop to the 50's at night in the summer.
I can distinctly remember some "experienced" member(s) here stating that climate makes no difference in oil, and oil selection.

Denial is an ugly thing.
 

nortones2

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DBW: "In Europe they live far enough north that the Xw30's serve them quite well year around. Seldom do they get above 86F except rarely in the summer, how many Europeans even have A/C on their houses much less their cars?"

Well some of us, in NW Europe, don't get 100F very often, but in more Southern, Continental climate areas, Madrid for example, sees 100F regularly in July, and all of August. Seville is hotter: right now the temperature is 38C (100F). http://tinyurl.com/lrae2y
I wouldn't dream of going to Greece or Crete at this time of year! :eek:
 

pleopard

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- all very interesting points. For piece of mind I'm almost compelled to switch back to 5W40, but I don't want to stray from the 505.01 requirement. I can still source Motul 8100 Specific 505.01 5W40, but probably not a whole lot else, unless I can figure out who sells the Fuchs oil I saw at Vagkraft in Brampton Ontario.
 

TornadoRed

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pleopard said:
...perhaps a better question is, have oils advanced enough that modern 5W30 oils can perform as well or better than 5W40, at least in modern engines? What are the technical reasons for running only 40 weights in the past? I find it much more difficult now to source 505.01 oil that's 5W40. As such, I'm simply running 5W30 (Total Ineo MC3 505.01). ...

Oils I can probably get are Motul or Fuchs 5W40 with 505.01 certification, but it will be a lot less convenient to get these oils.
Your 2006 TDI will be out of the powertrain warranty very soon, so there is no need for you to follow their guidelines with strict adherence.

A lot of PD TDI owners have switched to API CI-4+ or CJ-4 rated oils, which carry no VW specifications whatsoever. Others are adding ZDDP. No one can tell you what to do, you have to make your own decisions, but you've got far more options than you might have thought.

As for viscosity, many of the 5w30 oils are close to the lower end of the 40-weight range. Mobil 1 ESP Formula 5w30 is one of these. But I would still advise using the Mobil 1 ESP Formula M 5w40 instead.
 

pleopard

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Right. I do realize I have options, but I'm not sure just how comfortable I am running a CJ-4 oil. However, a 5W40 oil is what I believe may be best given that I do drive in temps above 86F and will do so even more frequently after I relocate to Williamsport PA in the next month.
 

velociT

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pleopard said:
Right. I do realize I have options, but I'm not sure just how comfortable I am running a CJ-4 oil. However, a 5W40 oil is what I believe may be best given that I do drive in temps above 86F and will do so even more frequently after I relocate to Williamsport PA in the next month.
Your motor will run smoother and quieter with TDT.

If that creates a remorse feeling.... perhaps some other vehicle is more for you.
 

pleopard

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Well, come on now... Many swear their engine runs quieter and smoother with fuel additives such as PS or Stanadyne. I've tried them both for many tanks and there's no perceptible difference to my ears. Nevertheless, I continue to use Stanadyne.
 

velociT

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pleopard said:
Well, come on now... Many swear their engine runs quieter and smoother with fuel additives such as PS or Stanadyne.
Haha while I do use PS, I'm not one of those people.

Fuel additives and engine oil are two waaaay different things... ;)
 

JettaSportTDi

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pleopard said:
Fair enough. I won't argue that. Anyway, I'm going to drive more and worry less.
H2SPORT in Georgetown sells Fuchs Titan oil for the PD motor 5L for $45.00
 

EddyKilowatt

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Drivbiwire said:
In the US very few regions permit the use of any Xw30, Anchorage AK may be one of the few places where you could safely run an Xw30 year around.
*cough* coastal california *cough* The land that summer forgot... and the reason I'm OK with 5W-30 in my ALH. First drain is out for UOA right now and the results will be really interesting (to me at least).

That said, even for the ALH I was on the fence about the thin stuff... and if I had a PD, I think the thinking time would've been 10X shorter, and the answer would've had a '40' in it.




 

Dimitri16V

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the difference between 5w-30 and 5w-40 in viscosity isn't that great.
if the 5w-30 is real synthetic , it shouldn't have a problem breaking down.
My old scirocco manual cautions about using 5w-30 in summer with high speed driving but I have used GC 0w-30 and the oil temps were actually lower. Now every VW engine is different, using a thin oil in a VR6 or a 1.8T will most likely cause damage since those engines run high temps intentionally for emmisions purposes.
 
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