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Isn't 5W-20 Wt. oil a little too light for a Turbocharged Engine?

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#21
After warm-up engine temperature is a constant - most modern engine are happy at 212F or 100C and then stay within 5 degrees of that.
Not according the AP oil temp reading on my car (which I know is a calculated value and not a raw oil temp reading). Even when warmed up it varies between 160 F and about 210 F (only seen during extended high speed cruise or aggressive driving). On top of that, I have about a 30 minute commute and it take at least 10 minutes to fully warm. I'd guess that overall, only about half of my driving is with a fully warmed up engine. I can't remember the last time I saw 200+ on the oil gauge.

In any case, most of the engine wear happens when the car is warming up, so that is the most critical period for protection. If most of your driving is with a warm engine at highway speeds in a warm climate (or if you use it primarily as a track car), a 5W-30 might be appropriate, but otherwise I don't see why it would be worth going against Ford's specs.
 


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#22
Not according the AP oil temp reading on my car (which I know is a calculated value and not a raw oil temp reading). Even when warmed up it varies between 160 F and about 210 F (only seen during extended high speed cruise or aggressive driving). On top of that, I have about a 30 minute commute and it take at least 10 minutes to fully warm. I'd guess that overall, only about half of my driving is with a fully warmed up engine. I can't remember the last time I saw 200+ on the oil gauge.

In any case, most of the engine wear happens when the car is warming up, so that is the most critical period for protection. If most of your driving is with a warm engine at highway speeds in a warm climate (or if you use it primarily as a track car), a 5W-30 might be appropriate, but otherwise I don't see why it would be worth going against Ford's specs.
According to ASDTM D5293 5W anything is all held to the same standard - as in the 5w30 and 5w20 are in the same viscosity bracket at startup and should have similar flow. Furthermore at temperature ASTM D445 determines that grades actually overlap that is to say the a thick 20 would overlap with a thin 30 etc. The high shear viscosity across 5w20, 5w30 and 5w40 is within 5% of each other. The reason for running Rotella T6 is that it is properly synthetic down to the last molecule, has one of the best additive package around, and it designed to deal with the higher temperature generated by the turbo. Ford Europe as I've mentioned for this same exact engine recommends either a 5w30 or a 5w40 so if listening to Ford matters to you - you still can.

PS - Your cooling system or your probe is broke if your operating temperature varies by 31%+
 


M-Sport fan

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#23
IF I am going to a 40 weight oil already, it is going to be either Red Line 0W-40, or Motul 300V 0W-40 Trophy, despite them being 2.5x and almost 4x the price of the T6 respectively. [wink]
 


neeqness

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#24
IF I am going to a 40 weight oil already, it is going to be either Red Line 0W-40, or Motul 300V 0W-40 Trophy, despite them being 2.5x and almost 4x the price of the T6 respectively. [wink]
What oil are you using now and what is your preferred weight if you don't mind me asking?

I've been sticking with stock oil for the engine so far as I'm new to DI, but the arguments here make sense and are convincing.
 


M-Sport fan

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#25
What oil are you using now and what is your preferred weight if you don't mind me asking?

I've been sticking with stock oil for the engine so far as I'm new to DI, but the arguments here make sense and are convincing.
I'm running the Castrol Edge EP (gold bottle/jug) 5W-20 with a FL 400 filter right now (first change @1200 mi.).

I have both the high TBN/long drain, Amsoil Signature Series 5W-20, and the shorter drain, but high ester base stock content Motul Specific 948-B 5W-20 stockpiled for the next two changes with many Amsoil EaO and Fram ULTRA filters.

Once it is out of power train warranty, I will go to some of the heavily additized to beyond GF5, GF6A?/SN, SP? whatever limits, Group 4/5 base stock, WAAYYYY beyond Ford 945-A spec 'boutique' oils, and will try some other weights as well (0W-30s, 0W-40s, and maybe even some great 0W-20s in the winter). [wink]
 


Zormecteon

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#26
The oil debate, which is around in almost every car community, never seems to end and no one ever wins.

Oil weight as dictated by the manufacturer will meet 90% of the criteria for their consumers. The other 10% may track their vehicle, drive it hard, or live in an area with severe weather conditions (extreme heat or cold). When that occurs, you may need to switch to a 5W-30 or 5W-40, even go down to 0W-20, 0W-30 and etc. to meet the demands you're putting on the car. But the only way to truly determine your engines needs is to have a used oil analysis performed to see if any additional wear is occuring. When that happens, step up/down one grade of oil.
The engineers have access to metallurgic analysis and computing power that we can only dream about. I don't think some guys sitting in their garage bench racing have a chance of coming up with better lubrication than the engineering team of a major automobile manufacturer. It's the same thing as in another thread about putting in a better spark plug. Ford wouldn't be offering the power train warranty only to recommend substandard lubrication.
 


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#27
IF I am going to a 40 weight oil already, it is going to be either Red Line 0W-40, or Motul 300V 0W-40 Trophy, despite them being 2.5x and almost 4x the price of the T6 respectively. [wink]

But can you buy them in a 55 gallon drum?

https://www.amazon.com/Shell-Rotella-550019901-Synthetic-Engine/dp/B00CQ3BQR0

But it seriously is nice have 20 dollar full synthetic oil changes - lets me feel good about flogging the car.
 


OffTheWall503

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#28
I use Mobil1 5W-20. It meets the Ford oil specifications necessary to maintain warranty and Mobil1 provides great turbo protection. You could use Mobil1 Extended Performance if you're worried about shearing, as it has a slightly bulkier additive pack.
 


neeqness

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#29

M-Sport fan

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#30
I use Mobil1 5W-20. It meets the Ford oil specifications necessary to maintain warranty and Mobil1 provides great turbo protection. You could use Mobil1 Extended Performance if you're worried about shearing, as it has a slightly bulkier additive pack.
Their EP oils might also use a slightly better base stock makeup than their non EP offerings as well. ;)
 


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#33
The engineers have access to metallurgic analysis and computing power that we can only dream about. I don't think some guys sitting in their garage bench racing have a chance of coming up with better lubrication than the engineering team of a major automobile manufacturer. It's the same thing as in another thread about putting in a better spark plug. Ford wouldn't be offering the power train warranty only to recommend substandard lubrication.
Just thinking out loud here, but if that were the case, why would Ford recommend different weights for different countries/markets? Not trying to argue, just opening the door for conversation!
 


M-Sport fan

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#35
Just thinking out loud here, but if that were the case, why would Ford recommend different weights for different countries/markets? Not trying to argue, just opening the door for conversation!
Along those same lines of thought (and one of the arguments FOR the heavily additized/group 4 & 5 base stock 'boutique oils on bitog) is that yes, the specced oils/standards will be fine and work well.

But, who's to say a more premium oil would not be even better yet (or at least NOT 'hurt' for those who want the 'warm and fuzzies' concerning their oil/engines, and are willing to spend the extra coin), and that those same engineers are SEVERELY CONSTRAINED by COST factors in what they choose to spec for a given engine, as well as all of the other parameters? [dunno]
 


OffTheWall503

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#36
Like I mentioned previously, you can always have a UOA performed if you think the oil isn't providing enough protection.

If you are using oil for a track day, then I imagine 5W-40 would be a great oil due to the abuse it would take and gives you better protection against shearing.

And actually speaking of good track oil, Mobil1 0W-40 would be a good track or aggressive daily oil since it easily shears to a 30 weight and stays there pretty well.
 


M-Sport fan

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#37
Like I mentioned previously, you can always have a UOA performed if you think the oil isn't providing enough protection.

If you are using oil for a track day, then I imagine 5W-40 would be a great oil due to the abuse it would take and gives you better protection against shearing.

And actually speaking of good track oil, Mobil1 0W-40 would be a good track or aggressive daily oil since it easily shears to a 30 weight and stays there pretty well.
UOAs are VERY inconsistent, and up until almost 20K miles, ALL engines will still show some (sometimes A LOT of) break-in 'wear metals', so they are NOT the end all-be all of engine condition monitors/checks.

There are also some 0W oils which do NOT shear much at all (or are VERY viscosity stable once they shear to a given point) yes, like the excellent M1 0W-40 you've mentioned, but also Red Line's 0W-40, Motul's 300V 0W-40, and MPT's 30K 0W-40, as well as some others I cannot think of right now.

A 0W does NOT instantly ensure that an oil shears down to water consistency! [nono]
VERY high quality viscosity index improvers, and pour point depressants DO exist, and when used in combination with naturally shear resistant group 4/5 base stocks make a VERY shear stable oil. ;)
 


Last edited:

Zormecteon

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#38
I agree about Mobil 1. A person can't go wrong using a better quality oil, but the viscosity ratings from the factory are most likely optimal. As to why the difference in different markets, interestingly enough "the book" on my Sprite (see icon) has different viscosity recommendations depending upon climate..(actually the prevalent ambient temperate) which could easily be read as location.
 


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#39
What about when you're doing a hybrid/big turbo upgrade? Should you step up to something like a 5w40 for daily driving because of the added heat/stresses? Just curious.
 


M-Sport fan

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#40
What about when you're doing a hybrid/big turbo upgrade? Should you step up to something like a 5w40 for daily driving because of the added heat/stresses? Just curious.
At that point you basically threw your power train warranty out the window (well, you might be able to 'fake out' some dealers/warranty reps with a very factory looking hybrid, at least until they open it up), so at that point you could use anything you want.

I would go to a 'stout' 0/5W-30 for daily use, and a 'boutique' (Red Line, Motul 300V, Millers, etc.) 0/5W-40 for open track/HPDE use.
 




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