Would 10w-30 ever be better than 5w-30?

[RandomInThe707]

This is a bit of a novice question.

Assuming good oil quality and equal top numbers, would an oil with a higher lower number ever be better than one with a lower number?

So, let's say 5w-30 versus 10w-30.

My understanding is both protect with the same viscosity on the high temp end. Yet, the 5w is more fluid at low temp, this offering better protection at lower temperature?

Am I thinking about this the right way?

In other words, what advantage would a 10w-30 have over a 5w-30?

Thanks.

 

[Bill in Utah]

Look through these results

I've used both and personally unless you are well below freezing you can use either. Since 5w-30 has come out that is all I use from well below zero to well above 100 degrees. Never a problem.

Take care, Bill

 

[modularv8]

10w30 will have a lower Noack %, less viscosity improvers. If you get synthetic 10w30, it will have a viscosity range near to 5w30.

 

[HTSS_TR]

Originally Posted By: modularv8
10w30 will have a lower Noack %, less viscosity improvers.


Specially dino. That why Honda recommends only 10W30 for S2000, until the model year 2005 they recommend 10W30 for temp above 0F and 5W40 for temp below 0F.

 

[bepperb]

Especially in a conventional it would be less volatile (noack) and less prone to shear. Modern oils this isn't a much of a concern, and with "synthetics" even cheap group 3 ones it makes it even less so. But 10~20 years ago it was significant.

I guess it depends if you were more likely to have cold start wear of shearing out of grade, but realistically they're more or less interchangeable at this point. Other minor issues like short trip fuel economy and HTHS might also be a factor one way or another.

 

[lewdwig]

www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1111303

This thread discusses oil consumption in a 3.5L Nissan.

 

[d00df00d]

Originally Posted By: RandomInThe707
This is a bit of a novice question.

Assuming good oil quality and equal top numbers, would an oil with a higher lower number ever be better than one with a lower number?

So, let's say 5w-30 versus 10w-30.

My understanding is both protect with the same viscosity on the high temp end. Yet, the 5w is more fluid at low temp, this offering better protection at lower temperature?

Am I thinking about this the right way?

In other words, what advantage would a 10w-30 have over a 5w-30?

Thanks.

Depends.

For example, it's possible to have a 5w-30 or even a 0w-30 with no viscosity index improvers (VIIs). That means it would have very high quality base stocks, which is a good thing in every way. In that case, you most likely wouldn't see an advantage to a 10w-30.

For most synthetics, even the ones that do require some VIIs in 5w-30 or 0w-30, there may be some advantages to a 10w-30. However, 9 times out of 10, those will be so slight that they will be outweighed by the disadvantage in cold pumpability.

On the other hand, if you're looking at dino oils, even good ones, then the advantages and disadvantages mentioned by other posters (volatility, shear stability, etc.) would usually apply.

 

[sangyup81]

Originally Posted By: RandomInThe707
This is a bit of a novice question.

Assuming good oil quality and equal top numbers, would an oil with a higher lower number ever be better than one with a lower number?

So, let's say 5w-30 versus 10w-30.

My understanding is both protect with the same viscosity on the high temp end. Yet, the 5w is more fluid at low temp, this offering better protection at lower temperature?

Am I thinking about this the right way?

In other words, what advantage would a 10w-30 have over a 5w-30?

Thanks.


No advantage if you are talking about Group III and higher oils. On the Group IIs, the 10w30 would be safer for Direct Injection engines

 

[JCCADILLACMOBILE]

Originally Posted By: RandomInThe707
This is a bit of a novice question.

Assuming good oil quality and equal top numbers, would an oil with a higher lower number ever be better than one with a lower number?

So, let's say 5w-30 versus 10w-30.

My understanding is both protect with the same viscosity on the high temp end. Yet, the 5w is more fluid at low temp, this offering better protection at lower temperature?

Am I thinking about this the right way?

In other words, what advantage would a 10w-30 have over a 5w-30?

Thanks.


According to this MAGNIFICENT FAQ, you want the "Thinnest Oil Possible."

Basically, it states that 5W-30 is the same as 10W-30 when Warmed, but VASTLY (!!!) Better at Start-up than a Honey-like Oil.. referring to any 40 or 50-weight.

He says "People think the Oil Tghinning as it gets Hot is the issue. in reality, the oil Thickening as it Cools is the issue."

90% of Engine Wear occurs at Start-up...

Who agrees with this? Making me feel MUCh better about 10W-30 in minw, maybe even 5W-30 all year !((() but i just read "Too Low" Oil Pressure can mean your Film is breaking down..

is 40PSI TOO LOW an Oil Pressure, where your Oil Film is at ricsk of breaking down.. at 3000RPM on a 5000RPM Redline Engine?


Here is the FAQ.. Hes bascially saying "Use Synthetic 5W-30 for Everything" and im thinking if i will do this, i WAS gonna use 5W-50 and i still may...

http://ferrarichat.com/forum/faq.php?s=0...otor_oil_basics

http://ferrarichat.com/forum/faq.php?faq=new_faq_item#faq_haas_articles

 

[chet2]

i would use 10-30 in a truck in warm weather

 

[biodiesel]

Originally Posted By: JCCADILLACMOBILE
Originally Posted By: RandomInThe707
This is a bit of a novice question.

Assuming good oil quality and equal top numbers, would an oil with a higher lower number ever be better than one with a lower number?

So, let's say 5w-30 versus 10w-30.

My understanding is both protect with the same viscosity on the high temp end. Yet, the 5w is more fluid at low temp, this offering better protection at lower temperature?

Am I thinking about this the right way?

In other words, what advantage would a 10w-30 have over a 5w-30?

Thanks.


According to this MAGNIFICENT FAQ, you want the "Thinnest Oil Possible."

Basically, it states that 5W-30 is the same as 10W-30 when Warmed, but VASTLY (!!!) Better at Start-up than a Honey-like Oil.. referring to any 40 or 50-weight.

He says "People think the Oil Tghinning as it gets Hot is the issue. in reality, the oil Thickening as it Cools is the issue."

90% of Engine Wear occurs at Start-up...

Who agrees with this? Making me feel MUCh better about 10W-30 in minw, maybe even 5W-30 all year !((() but i just read "Too Low" Oil Pressure can mean your Film is breaking down..

is 40PSI TOO LOW an Oil Pressure, where your Oil Film is at ricsk of breaking down.. at 3000RPM on a 5000RPM Redline Engine?


Here is the FAQ.. Hes bascially saying "Use Synthetic 5W-30 for Everything" and im thinking if i will do this, i WAS gonna use 5W-50 and i still may...

http://ferrarichat.com/forum/faq.php?s=0...otor_oil_basics

http://ferrarichat.com/forum/faq.php?faq=new_faq_item#faq_haas_articles


What is your obsession with shouting and punctuation abuse? Do a search for Haas. He's been discussed before.

Also, please dramatically reduce the size of the picture in your signature so that it doesn't take up the entire screen. Better yet, just provide a link to the picture instead. No one wants to look at your Jaguar each time you post in a thread.

 

[StrateLOSS]

I like looking at it.

 

[fdcg27]

Is there a prettier four door sedan than the Series Three XJ-6?