Does 5W-30 REALLY protect better than 5W-20?

Have the “I put M1 0w40 in everything” folks showed up yet?
Oh yea, we're here. :cool: M1 0w40 FTW!

But honestly... With all the recent topics on millions of thick vs thin threads, about viscosity spread, a 10w30 Synthetic may just be the answer to the "I want to use one oil for everything" crowd... That new Supertech Advanced Synthetic 10w30, the "20,000 mile oil", looks interesting, especially being under $20/5Qt...
 
When Ford first back spec'd 5w30 engines to 5w20 there was a GVW and towing proviso then the 5w20 is not acceptable. Why? It is fair to assume it to do with protecting the engine IMO.
Decide for yourself.
You nailed it. Sometimes all that is needed to answer a question is a common sense approach. IIRC that proviso is still in use in some vehicles.
 
Oh yea, we're here. :cool: M1 0w40 FTW!

But honestly... With all the recent topics on millions of thick vs thin threads, about viscosity spread, a 10w30 Synthetic may just be the answer to the "I want to use one oil for everything" crowd... That new Supertech Advanced Synthetic 10w30, the "20,000 mile oil", looks interesting, especially being under $20/5Qt...
I may just take this approach (one oil for both Hyundai). Maybe 5W-30. Gotta see what the maintenance package for the Tucson is like first.
 
Have the “I put M1 0w40 in everything” folks showed up yet?
Yo, right here, sorry I'm late! Many others are lurking, waiting to pounce once things get personal.

As far as the topic of the thread, will 5w-20 versus 5w-30 really matter? In your normal, everyday daily driver grocery getter driven in a sane manner, probably not a whole lot. You could turn the question around and ask "Is there a situation where 5w-20 would offer more protection or give some substantial benefit over 5w-30?"

I think Trav's answer pretty much sums up my thoughts.

I'd take it a step further and just dump in some M1 0W-40 and not worry about any of this..... :D:D:D
 
When Ford first back spec'd 5w30 engines to 5w20 there was a GVW and towing proviso then the 5w20 is not acceptable. Why? It is fair to assume it to do with protecting the engine IMO.
Decide for yourself.
Correct but it wasn't GVW but certain truck series. This was later changed with an updated TSB.
 

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Hyundai now puts 5w-30 syn in every 2.4L engine in its inventory now, and during dealer oil changes. I wouldn't be surprised if the 2.0L gets it too. There is a reason they do this.
That’s interesting … in my case, seems our 300 HP I4 (5+ quarts) needs 5w30 more than our 355 HP V8 (8 quarts) but it’s always an option to come up a grade at the end of factory warranty …
 
When Ford first back spec'd 5w30 engines to 5w20 there was a GVW and towing proviso then the 5w20 is not acceptable. Why? It is fair to assume it to do with protecting the engine IMO.
Decide for yourself.
Just to echo your point, the Ford 6.2 in a F250 spec’s 5w30. In a F150, it spec’s 5w20.
 
That’s interesting … in my case, seems our 300 HP I4 (5+ quarts) needs 5w30 more than our 355 HP V8 (8 quarts) but it’s always an option to come up a grade at the end of factory warranty …
Perhaps those extra three quarts are needed. Seems the older days of large American V8’s only required 6 quarts of type 1 oil, as well. They seem to have done fine with the type of oil available in their period. Similar I guess, with my 2.5q HD specifying 20w-50, while my higher revving 3.5q GS1100 required 10w-40.
 
Perhaps those extra three quarts are needed. Seems the older days of large American V8’s only required 6 quarts of type 1 oil, as well. They seem to have done fine with the type of oil available in their period. Similar I guess, with my 2.5q HD specifying 20w-50, while my higher revving 3.5q GS1100 required 10w-40.
The 5.3L was 6 quarts for years … so they went up 2 quarts at the 0w20 change - things my 2010 did not have (L83 has): variable displacement oil pump, oil cooler, and piston oil jets …
My L83 is quieter on 0w20 than my old one was on 5w40 …
Plan to stay on 0w20 at least for warranty period …
 
I always refer back to the differences in oil requirements that can be seen within a single manufacturer. Why do you suppose Ford recommends 5W-30 in the Focus ST, while all other Focuses get 5W-20? Why do they recommend 5W-50 in the Mustang GT if equipped with the "Track Pack" and you're planning to race it, but requires 5W-20 otherwise? Clearly they're encouraging owners to provide additional protection in extreme conditions, which tells me 5W-20 isn't up to the task. Having asked those questions, why would you not just provide the best protection you can, even if you're not racing, or even if you don't have a turbo? The sole purpose of 5W-20 is to achieve better fuel economy, and we're talking fractions of a mile per gallon. If you wouldn't put 5W-20 in your Mustang and go racing, why put it in at all?
 
I'm not comfortable with a 0/5W-20 in my cars. I'm old school and I'm using 5W-30 because it provides at least a little more wear protection and I sleep better for it.
 
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I know of several vehicles (trucks AND cars) that have over 300k miles on 5w20. Personally. I've never owned a car that long...
At present my 2007 Ford Fusion 2.3 has 270K using M1 20wt oils. I change it every 10K with only 2-4 oz of oil consumption. The cyl head is like new clean, and there is no sign of engine wear. My 2017 Fusion has 110K with 10K OCI. No oil consumption to date.
 
Don’t some of the GDI Hyundai engines have fuel dilution issues that require early oil changes? In which case I would use the 5W30 over a 5W20. Not even factoring in some of the other lubrication related issues Hyundai/Kia seems to be known for? School me.
*I just did my "COVID" non - standard oil change yesterday (one year / 2,700 mile) : The fuel dilution smell almost made me pass out as the oil drained ! ...In GDI I subscribe to 5W30 as in my case it probably sheered down to a 5W20 any way .
 
I always refer back to the differences in oil requirements that can be seen within a single manufacturer. Why do you suppose Ford recommends 5W-30 in the Focus ST, while all other Focuses get 5W-20? Why do they recommend 5W-50 in the Mustang GT if equipped with the "Track Pack" and you're planning to race it, but requires 5W-20 otherwise? Clearly they're encouraging owners to provide additional protection in extreme conditions, which tells me 5W-20 isn't up to the task. Having asked those questions, why would you not just provide the best protection you can, even if you're not racing, or even if you don't have a turbo? The sole purpose of 5W-20 is to achieve better fuel economy, and we're talking fractions of a mile per gallon. If you wouldn't put 5W-20 in your Mustang and go racing, why put it in at all?
Because they expect the ST owners to beat on their vehicles. It's a CYA movement by Ford (same for the GT).

Racing is an entirely different situation where any manufacturer will suggest a different grade for more protection.

Because it is entirely unnecessary and Ford also says to switch back to 5w-20 when not racing.

The difference in fuel economy between 5w-20 and 5w-50 is not fractions of a mile per gallon.
 
Hi,

Can folks here put an end to this debate on the Elantra forums? Some members are insisting that using 5W-30 instead of the more recommended 5W-20 will provide better engine protection and longer life.

So if there really any document evidence than this is true??

Thanks
Evidence? I would search for used oil analyses (UOA) for the specific engine and oil combinations that you're comparing. That's the only way to find real evidence of better protection. And keep in mind, with the UOA, the same engine can be driven in very different ways in very different temperatures, plus other variables such as maintenance, environment (dust), etc. that could affect the analysis results. But I hope you find what you are looking for.
 
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