# Oil Temperatures



## MrEddy (Jan 2, 2006)

Hello All,

Currently in my '12 Beetle 2.0T (70k miles) I'm running Motul 5W40. The oil has about 6000 miles on it now. To me it seems to run hotter than anything else I've run. 

We just got back from a 4700 mile road trip where the oil temp seemed to average about 220-230. It would get up to 240 in areas where the ambient temp was 90 or higher. I just made a short run to the store where I was going about 45 in 5th gear and it got up to 230. It's about 90 out right now.

Maybe I'm just getting old and the memory is going but I don't remember it ever getting over 220 regardless of the conditions. Makes me wonder if that's normal for this particular brand or is there something else going on.

Any thoughts?


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## Thy_Harrowing (Dec 7, 2014)

My thought is that it's just coincidence that it is running hotter around the time you switched to Motul. Not only have I run the same oil w/o said issue but, more importantly, from an engineering stand-point Motul would know if their oil tended to run hot and I doubt that would be their intention. You either got a bad batch or you have a mechanical issue. I find the latter much more likely to be honest. Anything else you can tell us?


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## MrEddy (Jan 2, 2006)

It seems odd to me as well but that's the only thing that changed when I noticed it. That's why I was wondering if anyone else had seen the same.

Overall everything seems to be fine. Coolant and intake temp (as read from an OBD2 Gauge) are good. I averaged right at 30MPG for the 4700 mile trip which is actually a little better than I have seen on previous long trips. It's running smooth and never misses a beat. Still had good power in the high heat of the desert and high elevation of the Rockies.


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## Thy_Harrowing (Dec 7, 2014)

Well before we get ahead to other things I want to take a step back and ask something I probably should have asked at first and not assumed... I'm not trying to be snarky/rude by asking this either by the way - you are sure your vehicle is equipped with an oil temp sensor and what you are reading is, in fact, the oil temps, correct? If so, where/what are you reading the temps from?


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## MrEddy (Jan 2, 2006)

Believe me I understand asking the seemingly simple questions. I'm a software engineer and deal a lot with integrating hardware with software and often have ask the "Are you sure it's plugged in?" question. You'd be surprised how often it's "No".

My Beetle came with a factory Oil Temp gauge. So it's whatever VW decided was important.


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## Thy_Harrowing (Dec 7, 2014)

> Believe me I understand asking the seemingly simple questions. I'm a software engineer and deal a lot with integrating hardware with software and often have ask the "Are you sure it's plugged in?" question. You'd be surprised how often it's "No".


Haha, actually I wouldn't be surprised! My father was a software engineer for almost 30 years and I heard all there is to hear haha. Not to mention, aside from cars, I have dabbled in computer hardware/software and PC game modding in my spare time from time to time and if I had a nickel for every time the answer to the simple questions about a mod was something other then "yes I did check that first"... well I'd be a lot more rich than I am on a teacher's salary! Software engineering is seeming a more attractive field by the month lately ($$$). But I digress...




> My Beetle came with a factory Oil Temp gauge. So it's whatever VW decided was important.


That's pretty neat. To be honest I didn't know for sure if VW had started equipping those as extras in newer models (haven't actually seen any OE ones before) or if you might have installed an oil temp system yourself like me. I am dubious about how accurate that gauge really is. As the coolant temp gauges are basically a dummy gauge good for only a rough idea of when coolant reaches N.O.T (and do not show nearly the same numbers as when you check via OBD2), I have to wonder if the same doesn't go for these. On the other hand, you are a software engineer and, therefore, I am sure well versed in testing/data logic so I'm confident that you have some relatively longitudinal data/meticulous observations with which to compare the current oil temp/ambient temp versus those of the past; that is to say, I'm going to assume that all other variables aside from the oil brand itself (e.g. the last time you ran another oil at 90F+ ambient temp) have been pretty well accounted for and considered already so we don't need to go over that.


If you trust the gauge and your observations/comparisons then things get more complicated from here. 


But honestly, before we analyze the situation further, you might consider calling Motul and bringing up the subject right with the source, see what they say. I'd be interested to know too. Might yield some good info, might yield nothing. Hard to say but it's worth a go to see.


Edit: I'd also like to point out that one of my first statement about the fact that I haven't seen oil temps that high is null. We have different motors and different setups so we can't really compare them. That being said, despite what I said in that same post about things from a "engineering stand-point" it is still technically possible that Motul is "supposed" to/does normally run a bit hotter in your engine but apparently not in mine. Which variety of Motul 5W-40 are you using, by the way?


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## MrEddy (Jan 2, 2006)

Thy_Harrowing said:


> That's pretty neat. I am dubious about how accurate that gauge really is. As the coolant temp gauges are basically a dummy gauge good for only a rough idea of when coolant reaches N.O.T (and do not show nearly the same numbers as when you check via OBD2), I have to wonder if the same doesn't go for these. On the other hand, you are a software engineer and, therefore, I am sure well versed in testing/data logic so I'm confident that you have some relatively longitudinal data/meticulous observations with which to compare the current oil temp/ambient temp versus those of the past; that is to say, I'm going to assume that all other variables aside from the oil brand itself (e.g. the last time you ran another oil at 90F+ ambient temp) have been pretty well accounted for and considered already so we don't need to go over that.


I know the OE gauges give you a filtered view of the actual data. The cars coolant temp always shows a steady 195 while the ODB gauge I have shows it varying from about 200 to 210. Unfortunately Oil Temp is not one of the parameters available through the OBD gauge so I can't get the same comparison. But I would think unless there's just something wrong with it that it's at least showing something close to correct. At least it does change unlike the coolant temp which we all know is never steady at a certain temperature. Even when the OBD gauge shows the coolant temp at 210 the OE one still shows 195. :screwy:



Thy_Harrowing said:


> If you trust the gauge and your observations/comparisons then things get more complicated from here.


Jury is still out but I'm leaning towards the Not Guilty side.



Thy_Harrowing said:


> But honestly, before we analyze the situation further, you might consider calling Motul and bringing up the subject right with the source, see what they say. I'd be interested to know too. Might yield some good info, might yield nothing. Hard to say but it's worth a go to see.


I'm going to hit their website up today and see what I can find since no one here seems to have had this issue.



Thy_Harrowing said:


> Edit: I'd also like to point out that one of my first statement about the fact that I haven't seen oil temps that high is null. We have different motors and different setups so we can't really compare them. That being said, despite what I said in that same post about things from a "engineering stand-point" it is still technically possible that Motul is "supposed" to/does normally run a bit hotter in your engine but apparently not in mine. Which variety of Motul 5W-40 are you using, by the way?


It's the Motul Specific 505.01/502.00.


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## Thy_Harrowing (Dec 7, 2014)

See what you wind on their website and/or a phone call. Next step I suggest would be to do an oil change and try Motul X-Cess 8100 and see what happens. I've researched and used a ton of different oils, all with Blackstone oil analysis samples afterward to analyze them, and when it came down to choosing between Motul Specific and Motul X-Cess. I don't remember the exact data figures and I don't remember the specifics of the research I did on the two as it was some time ago but, suffice to say, I was confident it is superior, if only somewhat. 

I'd also recommend posting this subject up on bobistheoilguy.com too.


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## a_riot (Jun 14, 2005)

Why don't you switch back to the former oil and see what happens? I know people say a standard is a standard, but it isn't really that way in the real world. Viscosity is only measured at two temps, 0 and 100, so who knows what happens at other temps, among many other variations. Without perfect information, you have to go with the evidence you have. If you changed to Motul and noticed hotter temps, then that's the hypothesis until further evidence suggests otherwise. I've had issues with Mobil1 0w-40 oil, even though it "meets the spec", and switching to a different brand resulted in less timing chain and valve train noise, and quieter cold starts, which typically means less wear, so I switched. The gauges in the car may not be reality, so if you have a way to check them, via software, etc, that's a good idea to make sure you don't have a cluster issue, etc.


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## MrEddy (Jan 2, 2006)

I'm almost due for an oil change now and I will be going to something else.

I suppose I should go back to the Pentosin that I had been using to see if I get the same issue.

Overall everything still seems to be running fine. We'll see what the different oil does.


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## Thy_Harrowing (Dec 7, 2014)

Gotta agree with a_riot. M1 is a case in point of how an oil can look good on the forums and on paper and even on blackstone analyses but that doesn't mean it is necessary good long term. I have used over half a dozen oils thag come highly recommended in the enthusiast crowd and have had all of them analyzed at least a couple times. A lot of people sing the praises of M1 0W-40 (and it is a good oil, good bang for your buck), even looks good on analyses, as good as higher tier more expensive oils. All that is well and good but personal observations are just as important and I had the same observation as a_riot, my motor is noiser eith that stuff and it also burns off faster than other oils, so I stopped using it. 

All this to say, don't just go with what you read online (ironic I know) but combine that with personal observations. If your observation isn't positive for Motul then forget it. For the record I gave Motul a couple runs and analyses and I'm not sticking with it either. Decided to go back to (and probably stay with) Liquimoly Leichtlauf 5W-40 (the blue bottle that says fully synthetic). LM has some other variants that look almost the same but I think the bottle is purple and isn't "fully synthetic".


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## surfstar (Mar 13, 2016)

M1 0w40 is currently $22.88 for 5qts at WalMart. Mobil is offering a $12 rebate, limit 2.

You will not get a better oil for your buck and your car won't know the difference between various VW 502 oils. Your wallet will.


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## Thy_Harrowing (Dec 7, 2014)

> You will not get a better oil for your buck


100% true.



> your car won't know the difference between various VW 502 oils


From a short-term perspective, yeah basically true. From a long-term perspective, not entirely true. However, provided OCIs are kept at the 5k-ish range then the choice of oil matters less either way.


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## surfstar (Mar 13, 2016)

Thy_Harrowing said:


> 100% true.
> 
> 
> 
> From a short-term perspective, yeah basically true. From a long-term perspective, not entirely true. However, provided OCIs are kept at the 5k-ish range then the choice of oil matters less either way.


Yeah, I'm mainly talking stock motors. Tuned ones may want a thicker or more specific oil and/or more frequent changes.


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## Thy_Harrowing (Dec 7, 2014)

> Yeah, I'm mainly talking stock motors. Tuned ones may want a thicker or more specific oil and/or more frequent changes.


They may, but even on a motor run stock its whole life it would eventually (again, long-term) see a difference based on your choice of oil run, even among 502 spec oils. Although, of course, that's just best logical deduction; I can't prove it since it's not possible to actually have completely controlled for and equivalent test scenarios for a longitudinal study to compare the difference of say M1 vs Motul (or similar). I can say this though, OCIs would definitely be a factor. For example, if those hypothetical test scenarios were run and the OCI for both cars was 5K then the margin of long-term difference you'd see between the M1 car and the Motul car would be smaller. Stretch that OCI to 10k and it'd be bigger. Reason being that some oils handle longer intervals better than others. M1 is an excellent all-around oil (especially for the price) but it has been proven to shear pretty fast; the Motul would have the advantage in the longer OCI tests because the M1 oil's additive packages and friction properties would break down a good deal earlier.

In any case, in real world OCI still matters far more than choosing among 502 spec oils, whether it's a tuned car or a stock car. Even on a stock car as long as you change your oil every 5-6k it will matter much less what 502 oil you use than if you follow VWs absurd 10k OCI claim. Folks are certainly free to disagree but for me, personally, it doesn't matter what VW says about 10k OCIs and it doesn't matter so much that modern synthetics perform better, longer; just because you CAN get away with 10k OCIs now doesn't mean you SHOULD, especially not repeatedly. You can be sure that even with a stock car if you keep it long enough you'll eventually be find complications of having always done 10k OCIs that you wouldn't find having done ~5k OCIs (particularly if you run an oil that shears fast like the M1).

Anyway... that's just my two-cents, no further comment. And, by the way, it was just as much or more for future readers' benefit, not for you guys; you guys seem to know your stuff.


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## PowerslavePA (Dec 9, 2014)

When you went from 5W30 to 5W40, it's a little thicker. The thicker the
oil is, the more heat, because it doesn't flow as fast to dissipate heat.

This is flow, not pressure or viscosity.

Still, as I said before, oil HAS to be above 210-degrees do vaporize moisture and contaminants.

I have used all kinds of oil grades, and never even worried about temperatures...

I am using 5W40 in my '15 TSI 1.8T.


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## SnakeEarl (Dec 11, 2013)

I usually run between 190 and 202 degrees for oil temperature. It is the same with both Redline 5W-40 and Liqui-Moly 5W-40. I think over 220 is a little high, but I'm not sure. I think the sensor can go up to 289 degrees and this is considered within range for diagnostics... Like someone else said, it needs to be hot to burn off moisture, but the temperature sensor/level sensor provides average temperature. Having the average temperature above 220 is abnormal in my opinion. I would try another oil. You could also try an oil analysis to see if there is abnormal wear from something with too much friction - causing higher temperatures. Or, it could just be a faulty sensor. You would need to use an infrared thermometer to check to make sure it is reading correctly.


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## PowerslavePA (Dec 9, 2014)

SnakeEarl said:


> I usually run between *190 and 202 degrees for oil temperature.* It is the same with both Redline 5W-40 and Liqui-Moly 5W-40. I think over 220 is a little high, but I'm not sure. I think the sensor can go up to 289 degrees and this is considered within range for diagnostics... Like someone else said, it needs to be hot to burn off moisture, but the temperature sensor/level sensor provides average temperature. Having the average temperature above 220 is abnormal in my opinion. I would try another oil. You could also try an oil analysis to see if there is abnormal wear from something with too much friction - causing higher temperatures. Or, it could just be a faulty sensor. You would need to use an infrared thermometer to check to make sure it is reading correctly.


That verified OIL temp at the sump, or what the coolant temp is? Once at operating temperatures,
oil will be 10-15 degrees higher than the coolant temp, but it takes longer for oil to get there than
the coolant. The colder it is, the longer it takes for the oil temp to pass the coolant temp. Oil will not 
get to complete operating temperature by idling either, you must drive.

That oil temp is low if sump. Engine oil needs to be at least 220 degrees F to burn off all the deposits and 
accumulated water vapor. For every pound of fuel burned in an engine, the combustion process also 
generates a pound of water! If engine sump temperatures rarely exceed 212 degrees (water’s 
boiling point), that water will mix with sulfur (another combustion by-product) and will create acids that 
can eventually damage bearings. So, if your oil temp never higher than 202 degrees, you have a problem.

A quality conventional motor oil will tolerate oil sump temperatures of up to 250 degrees, but starts 
breaking down over 275 degrees.

A full-synthetic oil will withstand sump temperatures in excess of 300 degrees, and for hard-core 
professional racing, some oval-track race teams are experimenting with ultra-thin, specially 
formulated, race-only synthetics operating at 350 degrees or even higher.


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## SnakeEarl (Dec 11, 2013)

That is average oil temperature in the oil pan based upon my oil temperature sensor. So, temperatures will be higher elsewhere, thus being able to burn off any water vapor. I have no oil-related issues.


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