Re: mobile 1

Yes, I would use it if the manufacturer specified it. But this is a Toyota forum, and to my knowledge that has not happened yet (and especially for the specific models mentioned in this thread).

If I ever did purchase a car that specified 5W-20, I might switch to Mobil 1 Extended Performance, which is not considered an energy saving formula compared to regular Mobil 1. This would give me the extra protection that might be needed with a 5W-20, and at the same time get better mileage than a regular 5W-30 synthetic.

My SO's 2007 RAV4 4 cylinder specifies 5W20 or 0W20. I have been using the API certified version of Mobil 1 (not the extended performance version) in her car. I think lots of 2007 Toyotas specify 5W20. Fords I have owned have been specifying 5W20 for a number of years. I used the Ford 5W20 syntehtic blend in my 2003 Expedition for as long as I owned it (90k miles) and never had any problems. When I sold the truck the engine ran as well as it did when new and it never needed any oil added between changes. The difference in fuel econmy between 5W20 and 5W30 is very small. I think Ford was claiming 0.3% (3 tenths of one percent). While this might be significant on a national basis, or for CAFE calculations, but I doubt you could detect the difference in everyday situations.

Ed White

I don't have the bottles in front of me to read, but I have to believe that both Mobil products are API SM. You would be hard pressed to find an oil that doesn't pass that minimum set of performance standards. Are you sure that Extended Performance isn't API cert? I thought that it surpassed it (like A5/B5)...?

It's the direction they are going.

Ford seems to have led the pack on the lower viscosity movement.

Good, since they grenade at exactly 100K :-)

Exactly.

Toyota MDT in MO

The Extended Performance version of Mobil 1 is not an "energy conserving formula" like the regular version.

In other respects Extended Performance Mobil 1 meets or exceeds the specs of regular Mobil 1. Both are API SM certified.

That's a new one. What I've always heard is that the wider the range the longer the polymer chains that form the molecules. In the "old days" the polymer chains broke down from the heat and stress and when they broke into smaller chains the oil loses it's higher viscosity. Then you wind up with an oil that thins out way too much at high temps, that leads to low oil pressure, thin films, further breakdown, and then it all just goes to hell and sludge forms.

Why not use synthetic and avoid these problems.

Honda was close behind. I read a couple of SAE papers on the advantages of 5W20. One was written by Toyota Engineers. The following quote is from this paper:

From SAE Paper 982506 -

"4. FUEL ECONOMY IMPROVEMENT WITH THE DEVELOPED 5W-20 OIL

"The fuel economy improvement capability of the 5W-20 oil was determined in vehicle testing with six engine types (after 10,000 km break-in) using the Japanese 10-15 and the FTP test modes. The test results shown in Fig. 7 compare fuel economy improvement of the SAE

5W-20 oil with a baseline SAE 5W-30 ILSAC GF-2 oil without MoDTC and sulfur compounds. The results clearly show that the SAE 5W-20 oil improves fuel economy by 1.2% to 2.0% as compared to SAE 5W-30 oil."

"4.1 FUEL ECONOMY RETENTION -

"...In initial operation, both the prototype and the fuel economy

5W-20 oils showed a large improvement of 3.5% over the 5W-30 oil. As operation continued, the prototype oil lost some of its effectiveness. However, the fuel economy 5W-20 oil retained its fuel efficiency at 5,000 km and only partially lost it at 10,000 kilometers...In another word, fuel economy improvement after 10,000km accumulation was more than 2.5% compared to the 5W-30 oil..."

"CONCLUSION

"The results of the studies of fuel efficiency of a newly developed SAE 5W-20, ILSAC GF-2 oil conducted with various types of modern engines show that:

"1. The optimum HTHS viscosity to improve fuel economy without increasing wear or oil consumption in typical Toyota engines is 2.6 mPa×s, which corresponds to the SAE 5W-20 grade..."

Ha Ha. I kept my first Expedtion for 150K miles and it ran perfectly when I traded it for the second. I belonged to an Expedition mailing list and many list member have Expeditions well over 200K miles.

Actually, the viscosity of motor oil usually increases with age and usage - it becomes thicker, not thinner (assuming there is not a problem with excessive blow-by).

Ed

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Ed, I think Ashton is talking about oil thinning as the engine is being used and the oil heats up. Oil, of course, thins as that happens. But I agree with you that over longer time frames--weeks and months--oil degrades from use, cold, etc. and the viscosity of the oil can increase/thicken from it original visc.

I think you and he are just talking about different time frames and conditions, so you're both correct :-)

That's what I do myself. I was just saying how the wide range dino oils achieve their wide range.

What Well-Built said.... I was only talking about the old 10W40 oils that were massively filled with long chain polymers to achieve the wide viscosity range.

Comboverfish wrote in article ...

Peruse the motor oil aisle at your friendly local Wally-World.

They are now marketing older, out-of-date API spec motor oil for "older" cars.

This is NOT like the Pennzoil or Valvoline that is marketed as having been designed with additive packages for older cars.

This stuff is, simply, out-of-date, non-current API spec oil.......

Well, its actually an all-makes forum as well. Look where its being posted.

Which are snake-oil anyway...

Which can actually make the oil better for certain applications, so long as it was a decent oil to start with (though most of the ones you're describing aren't). The current API specs require lower percentages of certain additives, particularly ZDDP, which are critical for engines with high-pressure sliding contact points- things like non-roller cam followers and gear drives of various types.

That's why a lot of us with vintage cars have switched over to using diesel-spec oils (Shell Rotella, Mobil Delvac, Chevron Delo 400, etc.) instead of the latest "greatest" API spec'd gasoline engine oils. Even the diesel oils are having their percentages reduced, but not as quickly as the gasoline-engine spec oils.

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If you want lots of ZDDP, you might want to try the RLI Bio-Syn oils (RenewableLube.com).

IIRC, their oil has about 2,000 PPM (parts per million) of phosphorous and zinc (engine wear protectant additives). Can't say for sure if this much would eventually harm your catalytic system.

The OP asked about a specific Toyota model.

No, it is not an all makes forum. People post about politics also, but that does not make this a political forum.

rec.autos.tech does seem to be flooded with huge quantities of Toyota problem posts lately. Which is hilarious, because I always heard that those things "never broke down." :-p

Yes, it is. I was referring to rec.autos.tech... which is definitely about all manufacturers. I don't read alt.autos.toyota except for all the cross-posting that goes on. And when I reply, I try to keep it general if its also going back to .tech as well.

If 0.1% of the Toyotae break down each year, then that is around maybe

25,000 a year.

Toytota sells more cars around the world than anyone else.

Jeff