Mobil 1 5W-30 -vs- 0W40

[dragboat]

Good post Al. Those Enginneers are far removed from what the owners manual suggests or demands in most cases.Europe is a distant Planet. This is the USA with EPA,CAFE in the mix

These motors are built,then hopefully as a knowledgable consumer a oil is chosen to use in them, not the other way round as in motors are built for a specific oil

Eric, Of course it is your call but I recommend the 10/30 Supersyn in winter and then prove it's worth in summer through analysis. You might be surprised what it will do,especially for the first 90k or so,as the motor wears you could step up in viscosity then. Next summer you could analize th 10/30 and see if it was holding up to your driving style/engine needs.

Good luck in what you decide on and please post the oil you chose,often we never hear back about it

 

[dagmando]

Do what the manual says...period. This is a brand new car under warranty, why mess with it. It is designed to run with the 5w-30 the manual says, NOT 0w-40. Please take what people say here with a grain if salt, they are not Mazda experts.

 

[Eiron]

TooSlick, up until about a month ago I agreed with your position 100%. The manual for my '90 Saab says to use 10-30, & my '99 says to use 5W/10W-30. (I think the '03 manual says 0W/5W-30.) Then I discovered that Saab released a Technical Service Bulletin OVER 2 YRS AGO that changed the engine oil recommendations for all years, makes & models going back to the late '70s. Now it's (in descending order of preference) 0W-40 full-syn (also factory fill), 5W-30 semi-syn, & 10W-40 mineral (not for turbo or diesel). These are all dealer-supplied oils. The problem? Only the 5W-30 is provided to US dealers! The others don't even have US part numbers! Learning all of this, I've changed my opinion about what to use in my car & no longer believe the manual to be solely based on what's best for mechanical longevity (i.e., CAFE).
EW, I agree with dagmando's concern for warranty issues. I think a void is based on whether or not the substituted item caused the failure, but I'd suggest you talk to Mazda about it specifically.
In my '90 (2.0L, 125HP, non-turbo, similar rev range) I've been running 10W-30 for the past 4yrs/50k mi. Because of what I've learned (above), my desire to run extended drain intervals (10k mi each, for the past 40k mi), & the fact that it's using about 12oz between drains (it's got 160k on it), I just put in M1 15W-50. If it were new, like yours, I'd only use 0W-40. I live about an hour north of Denver, & it sounds like the climate is similar to yours. (No heated garage, though

)

 

[Dr. T]

I think there's 2 issues that need to be understood here. Firstly, 5-30 is generally a US grade designed for fuel economy and shorter change intervals (eg. 3k) while driving at speeds under 65mph. If you're changing your oil out at 3k with M-1, then it should suffice. This is the general consensus, and this is what's done in the U.S.. This sounds like it's applicable to your application.

However, in other parts of the world, where they don't believe in replacing the oil every month or two "just because", where the price of the average oil is $10/qt. and where there is a concern for conservation of expendable "environmental resources", a higher grade eg. 5-40, 10-40 will provide added gusto to last to 7-10k mi. in addition to providing protection at speeds of 100+mph. This is why Eur/Aus. has different requirements.

And remember, none of these "recommendations" are for synthetic oils per se. They are blanket recommendations. So if you plan on changing the oil every 3k mi, then a 0-40 may be overkill. But, if you plan on going with higher mi. intervals, it may be beneficial. Then again, you could probably do this with either grade of M-1. I would start with the M-1 5-30....if you have very little to no consumption after a couple changes, then stick to it, otherwise move up the grade scale. But, IMHO 3k intervals are simply a waste of time/$/resources particularly in a new/unworn engine.

 

[ewsmith1]

Wow!!!

I am getting some great info here....

I find it funny that what appears to be the same engine (2.0L 130/131 HP) in Australia calls for a 10W-40 oil when the American version calls for 30 weight.

I am going to email Mazda and ask them if it is the same engine...it will be interesting to see what they say.

Sprintman...thanks!

Thanks to everyone and please keep the opinions coming.

Eric...

 

[Ross]

Please inform me...

I have always used M1 5w30 in my cars until they reach about 90,000 miles, then I swith to M1 10w30. I have read the forum about how good M1 0W40 is, but I thought that X-W40 weight oils weren't recomended in todays tight tolerance engines. They are just to thick at higher temps.
I also thought that that oils that have a big differnce bewtween the first and last #'s (the 5 and 40 in 5W40) were not as good as oils having a smaller difference. Also wouldn't a 0W oil be more likely to leak from a seal than a 5W oil.

So in conclusion, is M1 0W40 better over all in my 2000 caravan 3.3L than M1 5W30. I change oil about every 4-5K, and currently do not notice any measurable oil consumpition between oil changes.

Thanks for your advice....

And gosh darn it, I just bought 2 cases of M1 5W30 tri-syn at walmart..

 

[spectre]

As i reported in another thread concerning m1 0-40 ss, i suspected i lost 3-4 mpg's in a 2002 cavalier with the new ecotech 4 cylinder engine. I changed back to Mobil 1 5w-30 about a week ago and i am pleased to report my mpg's are back to where they were...
Since i commute over 500 miles a week, 3-4 mpg's mean a lot to me.

Miles are 99 % interstate, so i will continue changing at 5k miles.

 

[TooSlick]

Spector,

You will lose some performance using thicker oil in a high revving engine. The pumping and frictional losses are greater at higher rpms. I am very surprised at the extent of the mileage drop in this case. If you ran the 0w-40 in a low rpm V-8 engine, you might not notice the difference at all in fuel efficiency

Al,

Motorcycles with wet clutches tend to badly shear the oil in the transmission and run significantly higher oil temps than cars. Quite honestly it is a misleading comparison.... Most air cooled, V-Twin bikes actually call for 20w-50 grades, but you wouldn't want to run that in your new Honda or Toyota ....

This 5w-30/10w-30 stuff isn't the big sham it is made out to be - I certainly don't see modern engines wearing out prematurely. These engines are designed to provide adequate oil pressure with 5w-30 grades and design changes have been made to the valvetrain to reduce the magnitude of the loads, such as roller lifters.

TooSlick

 

[dragboat]

spectre,

Those are very easy miles it seems. I would be very interested in seeing a oil analysis. Do you have plans to do so? That M1 might go 8k or so safely with that type driving and that engine design.A test at 5k would give a very good idea what it could go to.

 

[VaderSS]

quote:

---

general consensus

---

One of my pet peeves.
Consensus = General agreement so general consensus = general general agreement.

I've been running M1 0W40SS in my LT1 powered Impala and have noted no difference in mileage or anything else between it and 5W30TS. I am also seeing less oil consumption.

That said, I was very pleasantly suprised to see that M1 5W30TS held up very well in my application, with virtually no shear and low wear and low nitration/oxidation numbers at 4k when the change oil light lit.

I have close to 5k on the 0W40 now, and it still is a nice transparent dark amber color. I have run more highway miles than normal, so the change oil light has not lit yet. When it does, I'll pull a sample for comparison with the 5W30.

 

[VaderSS]

The oil monitor circuit looks at variables such as open lop or closed loop operation, temperature, RPM, etc.

The worst case I've had was 4k and the best has been 6500. It is WAY conservative for synthetic, but probably right on for an SH dino 5W30.

I use it for testing the oil, so each sample will be equally stressed. 4k on this oil would not be as hard as 4k on the last interval...

As for as the 0W40 being thinner on startup than say a 10W30, cold 0W40 is still thicker than hot 10W30, so why would it leak more?

 

[dagmando]

Vader SS: Does you car have the oil change monitoring system that is automatic? How does it know when to change? Driving habits, cold starts?

 

[Eiron]

Ross,
We're sorta drifting away from ew's situation, but I think what you're doing is fine. If anything, you might change to the M1 0W-30 until your planned switch at 90k, since it's marginally heavier at both 40C & 100C than the 5W-30 is, & it'll flow better at start-up in the depths of a Bismark winter. (And, if you never see any oil consumption, you may never want to switch!) From what I've heard, the vis spread on the new (SL) oils is not a concern like it was a couple of yrs ago. And I'm not so sure that the biggest concern is seals leaking on an older engine using a 0W as much as it is blow-by when you first start it up. (Anybody...?)

 

[ewsmith1]

Great Nezter,

Are you saying the Mobil 0W-30 has a thicker visc "number" than the 5W-30???

I know the 5W-30 is right around 9.8-10????

What is the 0W-30?????

Thanks,
Eric...

 

[ewsmith1]

Well,

I got a reply from mazda...I asked them if my car had the same engine as other mazda cars around the world sold under the same name or slightly different designatons.

Although the other cars appeared to have the same engine via specs given, mazda said this...

"We cannot comment on our cars sold outside north america"

Basically, I wanted to know why the same engine outside the country had a different SAE oil recommendation...I asked them about this over the phone and they played dumb. I asked them about the EPA and CAFE, which they acted like they had never heard of.

O'well, I guess I'll have to use the info I have gained here to make my choice on SAE grade.

Thanks,
Eric...

 

[sprintman]

ewsmith1
Make no mistake the only difference between a Mazda here/anywhere and the U.S was the ships name they loaded it on. 0W40 TS seemed like a top oil, hopefully the SS version will be better?

 

[Eiron]

Sorry, those Pumpability Limit numbers should read as negative numbers. (correcting too many typos at once

)

 

[ewsmith1]

Greg,

Thanks for the info...I am amazed that the 0W-30 is a slightly "heavier" oil at operating temp.

After I change the oil to 0w-30 (if I can find it), I am going to due an oil analysis at about 3000 miles of usage.

I have Blackstone labs sending me a sample collecting kit and plan to us them.

Thanks,
Eric...

 

[Roadster]

Hey Eric - Congrats on the P5. I also have one - red, sun roof, 5 speed, side air bags, polished wheels...

I am running Royal Purple 5w-30 and will do an oil analysis at 10,000 miles or 5000 on the oil.

So, having fun scaring the wife in the corners with the P5

Phil

 

[Jay]

Good try, though, e.w.