Question about grade OIL.

[dreamerx]

Hello.
Today I see a toyota corolla (2001) user manual, but when I see the oil recomendation I got a little confused.
isn't the 5w-30 and 10w-30 oil protecting the same in work temperature?
why is the 10w-30 covering full range of temperature and the 5w-30 ?

Thanks in advance.

 

[Polly_3SFE]

The 10w-30 is not covering the full range of 5w-30. The diagram depicts that 5w-30 is recommended for startup protection for below zero temperatures, or if the climate in your area is frequently -20 to 40°F. Counter-intuitively, you can see that the the diagram depicts 10w-30 is recommended for climates that frequent 50 to 100°F. You are correct in that the viscosity of the two oils is the same at operating temperature.

Others would have a more scientific answer, but the reasoning behind the recommendations is the extreme climates' impact on the viscosity of the oil in your car when its been sitting outside in the cold or heat. Extreme cold will have a thickening effect, which is why the lower startup viscosity oil is often recommended for winter. Extreme heat will have a thinning effect, which is why the higher startup viscosity oil is often recommended for summer.

 

[Kuato]

Both oils are the same at operating temperature. But 16 years ago, 5w30 was not as stout as it is today(which is why not recommended for higher temps) but flowed better at cold temperatures than 10w30.

 

[Linctex]

Originally Posted By: Kuato
But 16 years ago, 5w30 was not as stout as it is today


Are you SURE?!?

Remember, 5W-20 was coming on the scene (Honda and Ford) right about this time 16 years ago, and I think it was SL or SM. Hardly what I would call "not as stout".

I would run 5W-30 in this car in weather far, far, far warmer than 50*F and I wouldn't be worried even 1 iota.

I'm surprised they allowed 20W-50 to even exist on this chart.

 

[aquariuscsm]

I'm one that always sticks to the manual. I'd use 10W30. 5W30 appears to be the extreme cold climate recommendation,and 20W50 being for extreme heat. 10W30 looks to be the median cold,warm,and hot recommendation.

 

[SwampSurvivor]

Originally Posted By: Linctex
Originally Posted By: Kuato
But 16 years ago, 5w30 was not as stout as it is today


Are you SURE?!?

Remember, 5W-20 was coming on the scene (Honda and Ford) right about this time 16 years ago, and I think it was SL or SM. Hardly what I would call "not as stout".

I would run 5W-30 in this car in weather far, far, far warmer than 50*F and I wouldn't be worried even 1 iota.

I'm surprised they allowed 20W-50 to even exist on this chart.


16 years ago, 5w-30s would shear down to 5w-20s pretty quickly. 10w-30s would stay a 30 grade.
That's not the case so much now.

 

[CharBaby]

Keep in mind, when the '01 Corolla's owner's manual was written and the quality of our conventional motor oils in 2001(SJ/GF-2). BTW, it was good quality for back then but only approaching Group II and most were still Group I. We weren't at SL/GF-3 until about 2004.

http://www.api.org/~/media/files/certification/engine-oil-diesel/publications/mom_guide_english_2013.pdf

 

[cmhj]

Remember when this was printed!!! What were oils pecs then? Etc etc

 

[FCD]

Modern synthetic 5W and 10W-30 oils will protect just about equally as well at high temperatures nowadays.

 

[Bgallagher]

Originally Posted By: aquariuscsm
I'm one that always sticks to the manual. I'd use 10W30. 5W30 appears to be the extreme cold climate recommendation,and 20W50 being for extreme heat. 10W30 looks to be the median cold,warm,and hot recommendation.


+1 I wouldn't be concerned about colder weather in FL. I would use any 10w-30 and enjoy. You can use a 5w-30 but that is up to you. Personally I would stick with a conventional 10w-30

 

[SwampSurvivor]

On a 16 year old Corolla, I'd just go for whatever is cheapest.

 

[Kuato]

Originally Posted By: Miller88
Originally Posted By: Linctex
Originally Posted By: Kuato
But 16 years ago, 5w30 was not as stout as it is today


Are you SURE?!?

Remember, 5W-20 was coming on the scene (Honda and Ford) right about this time 16 years ago, and I think it was SL or SM. Hardly what I would call "not as stout".

I would run 5W-30 in this car in weather far, far, far warmer than 50*F and I wouldn't be worried even 1 iota.

I'm surprised they allowed 20W-50 to even exist on this chart.


16 years ago, 5w-30s would shear down to 5w-20s pretty quickly. 10w-30s would stay a 30 grade.
That's not the case so much now.


Yes linctex, I am sure.

 

[Linctex]

Originally Posted By: Miller88
On a 16 year old Corolla, I'd just go for whatever is cheapest.


I think this comment is probably the most valid, LOL!

 

[mjoekingz28]

So just trash it since it is old(er)???

Maybe some folks want their cars to make it to classic status and beyond.

 

[Polly_3SFE]

Cheap oil shouldn't trash it, as long as it is the correct viscosity and meets modern API standards.

 

[QSUDFrostedFlake]

Originally Posted By: Miller88
On a 16 year old Corolla, I'd just go for whatever is cheapest.


But in the correct grade of 10w-30. Heck, even Family Dollar has that stocked. I saw a lone/solo tempting QS Defy(not the High Mileage one)on the shelf and a bunch of the semi-syn Adv Dur, but I thought to myself, I do not want to introduce Zinc as an anti-wear into my concoction.

 

[bmwpowere36m3]

Originally Posted By: mjoekingz28
So just trash it since it is old(er)???

Maybe some folks want their cars to make it to classic status and beyond.


A classic Corolla... haha. But seriously, can't go wrong with ANY 5W-30 or 10W-30.

 

[QSUDFrostedFlake]

This chart is not only the reason but vindication and validation for using 10w-30 in my climate year-round.