thickest 20 weight

[wjli]

I tried to search but came up empty, plus I know many of you have tons of knowledge you are itching to share....so, who has the thickest 5w20 conventional oil at this time ? I played with the idea of going to a 5w30 in my 20 weight spec'd cars just to experiment with smoothness/noise reduction etc. but I know the norm used to be that a 30 weight soon sheared down to a heavy 20 weight anyway (not sure if that is still true) so I would just be as well going with a heavy 20. Thanks for your insight on this one.
Also, one more question for cold starting, would a "conventional" 5w20 be close in terms of cold flow to a "synthetic" 5w30 (since synthetics supposedly thicken less than conventional) Or is the gap still pretty wide. when I say cold flow I mean something like 30F, not super cold. Thanks again.

 

[TFB1]

Castrol GTX is probably the thickest 5W-20(at least on this chart, just slightly below 30W territory)...

If I wanted to try for quieter/smoother, I'd use a 5W-30 with a cSt of at least 10.5...

http://www.pqiamerica.com/Feb2014/consolidated5w20ALL.html

 

[HTSS_TR]

If you replace 1 quart 5W20 with 1 quart 15W40 your mixed will be a heavy 5W20.

 

[zach1900]

Or you could accept the fact that all oil looses and gains viscosity with use.

 

[901Memphis]

Just use a 5w30

 

[donnyj08]

Amsoil OE 5w20 is a thicker 20wt with its HTHS of 2.8

 

[hatt]

If you want a thick 20 simply buy an ILSAC rated 5/10w-30.

 

[Jetronic]

http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3860341/Gulf_formula_GMX_5w-30

here's a selection of 5w30 that are supposed to be extremably shear stable, yet thin at 30F

One is a full saps, the other a mid-saps, depending what you require.

I haven't found any oils offering the same level of wear protection but thinner viscosity.

They're not conventional though.

 

[slacktide_bitog]

Probably Redline

 

[stchman]

Kind of sounds like a lot of 5W-20 oils are not actually 20 weight. How can they be 20 weight oils if they are not?!!!!!

 

[Merkava_4]

Just go with a synthetic 5W-30 and you won't have to worry about shearing.

I don't see how people can tolerate the noise those 20 weights make.

 

[Justin251]

The lightest 30wt?

 

[SR5]

Yep the heaviest 20wt, is a light 30wt.

Get a full synthetic ILSAC 5W30. The ILSAC grades are light 30wt oils compared to the heavy A3/B4 or HDEO 30 Wt oils.

Which 5W starts better? You have to look at the spec sheets. But 5w is a range, and some recent data I read here showed a 5w conventional closer to the top of the range and the full synthetic closer to the bottom (easier cold starting). But this was for below 0F, at 30F they should both be fine. Even a 10W will be fine above 0F.

 

[stchman]

Originally Posted By: Merkava_4
Just go with a synthetic 5W-30 and you won't have to worry about shearing.

I don't see how people can tolerate the noise those 20 weights make.


There will be no audible difference in an engine between 5W-20 and 5W-30. To say otherwise is absurd.

 

[Shannow]

Originally Posted By: SR5
Yep the heaviest 20wt, is a light 30wt.

Get a full synthetic ILSAC 5W30. The ILSAC grades are light 30wt oils compared to the heavy A3/B4 or HDEO 30 Wt oils.

 

[meborder]

Originally Posted By: stchman
Originally Posted By: Merkava_4
Just go with a synthetic 5W-30 and you won't have to worry about shearing.

I don't see how people can tolerate the noise those 20 weights make.


There will be no audible difference in an engine between 5W-20 and 5W-30. To say otherwise is absurd.


Color me absurd,then.

The ole 5.4 is MUCH quieter on 5w30 compared to the 5w20, particularly the timing chain.

 

[Merkava_4]

Originally Posted By: stchman
There will be no audible difference in an engine between 5W-20 and 5W-30. To say otherwise is absurd.


I hope you're not betting your life on that statement. Viscosity plays a major role in lubrication and the sound (or absence of sound) is a testament to how well the engine is being lubricated.

 

[Luisraul924]

Originally Posted By: Merkava_4
Originally Posted By: stchman
There will be no audible difference in an engine between 5W-20 and 5W-30. To say otherwise is absurd.


I hope you're not betting your life on that statement. Viscosity plays a major role in lubrication and the sound (or absence of sound) is a testament to how well the engine is being lubricated.


While I don't agree with the second part about "how well the engine is being lubricated". There is definitely a difference in audibility of engine oils.

 

[crazyoildude]

In most cases there is a sound difference between 5w20 and 5w30 I can hear the difference.

 

[zeng]

Originally Posted By: Merkava_4
Originally Posted By: stchman
There will be no audible difference in an engine between 5W-20 and 5W-30. To say otherwise is absurd.


I hope you're not betting your life on that statement. Viscosity plays a major role in lubrication and the sound (or absence of sound) is a testament to how well the engine is being lubricated.


IME tends to agree with you ....