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killing time in walmart looking at oils and ran into this Mobil 1 5w40. Is this new or old oil formulation. 10k v 15k. whats the difference in base oil?
Mobil 1 5w40 change or no?
- Thread starter thickvthin
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SQ. it's updated to that but it might be the same old formulation with just an api update and a stretched interval as long as the manufacturer allows it but they know most don't. I'll see if there's an updated pds with a difference of typical values compared to the old one if they also updated that at the same time since they sometimes don't. If it's the same price as the 0w-40 i'd rather get the 0w-40 instead. Same goes for castrol. 5w-40's aren't bad but are less good and should be priced accordingly.
Both are the same price at my local Wally. That being the case, I'll reach for the 0W-40.
It is.
there is the particulate filter friendly version, ESP.
I don't think it comes with a major tradeoff
In my opinion, unless you live in a very cold climate, Mobil 1 Full Synthetic 5w40 is a slightly better choice than Mobil 1 Full Synthetic 0w40. I believe that based on the similar specifications met and results in this thread:
Link
I would buy neither, and instead choose Quaker State 5W-40 or Pennzoil Platinum 5W-40. If lower SAPS is acceptable to you, I’d also include Mobil 1 ESP 0W-30.
Link
I would buy neither, and instead choose Quaker State 5W-40 or Pennzoil Platinum 5W-40. If lower SAPS is acceptable to you, I’d also include Mobil 1 ESP 0W-30.
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does gtl stick to engine better after shutoff?
Yes, very well. Not as well as esters, but neither of these oils are known to contain any.
After shutoff though, it's both the base oils as well as the antiwear additive layer, since it's in boundary lubrication (no oil pressure until the engine/oil pump is moving).
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so is Quaker State 5W-40 or motul gen 2 excess , but they are some of the most preferable oils here.
remember final product matters at the end.if it works then its good.
yes but cooking oil on the stove is similar to comparing them at the ice luge: totally irrelevant to what 'works.'
at the end of the day thats all that matters.
since we are speaking with cooking terms, one thing is recipy ,the other thing is the result.
repsol says is using PAO for their recipy ,specs are good ,result is mediocre.
Quaker State 5W-40 or motul gen 2 excess dont but we have testimonials they work better than other PAO oils.
shell helix 5-40 here in europe is one of the most good selling oils.if it didnt work they wouldnt use it.
and its the same as Quaker State 5W-40.
so yes if it sells ,it works,if it works then its a good oil ,no matter what recipy.this is for us here that split hairs.
most drivers dont judge by recipy,they dont bother to know.
best-selling is also not relevant to what 'works.' as you say, "most drivers dont judge by recipy,they dont bother to know."
and since you are replying to me, it's important to note you were the one that brought up Quaker State and motul. I was comparing Mobil 1 Full Synthetic 5w40 to Mobil 1 Full Synthetic 0w40. In which case I do not believe there is any serious debate, except in the "which oil boils more on the stove" test. Mobil 1 Full Synthetic 0w40 is the clear flagship product for Mobil 1 Euro full saps oils. if you're going by 'most good selling' then that would also be Mobil 1 Full Synthetic 0w40 based on the online marketplace here.
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Your viewpoint that you keep stating warrants a response from me. I do not boil oils on a stove. I do volatility measurements and state the approximate temperature for each test. The temperature is well below the boiling point. After doing the volatility tests, I continue the test without weighing the oils. The purpose is to continue oxidizing the oils and observations are made about deposit and insolubles formation. The test is obviously not completely representative of what oils experience inside of an engine, however oils in my tests and in engines both experience oxidation.
Presence of PAO in Mobil 1 Full Synthetic 0W-40 and lack of it in Mobil 1 Full Synthetic 5W-40 certainly does not make the former generally superior to the latter. Studies decades ago and posted here in the 2000s proved that. The PAO is what allows it to meet the 0W requirement and stay within the 10% Noack limit imposed by MB 229.5. Mobil 1 0W-40 certainly is more volatile than the 5W-40. That does not automatically make it generally worse but it does indicate that the 0W-40 has a lower combined base oil viscosity and higher VII contribution. If the same VII type(s) are used in both oils, the 0W-40 is less shear stable. My tests showed that the 0W-40 had significantly more insolubles than 5W-40. They are a result of oxidation/polymerization reactions.
I think 0W-40 oils are popular with Euro automakers because it is suitable for use in almost any location on Earth that cars are driven. 0W-40 also favors fuel economy compared to a similarly-formulated 5W-40 because of generally having lower permanent and temporary shear stability. Oils are full of pros and cons. An oil that is superior in one use case and criteria one most cares about often is inferior in another.