Aside from fuel dillution which obviously dillutes/thins any motor oil regardless of weight...and the fact that many synthetic 5w30's and 10w30's are very close in cold pumpability (i.e. PP 5w30 and 10w30 are very close) does it make sense to anybody to just use 10w30 year round even in cold winter? My reasoning is this,.... from what I understand about oils is that whether dino or synthetic the manufacturer must add more viscosity improvers to get a larger viscosity spread to reach a 0w30 or 5w30. And these VI's actually break down with time, and cause oxidation, and thicken. I see alot of uoa's with viscosity thickening slighlty after time, so your 5w30 after it thickens also effects your cold pumpability, not a 5w30 anymore, but maybe a 10w30 or even higher? I am wondering if just running a 10w30 will not thicken as bad as a 5w30 or 0w30. I had thickening problems awhile back with Amsoil 0w30, and HDD 5w30, but never tried their 10w30. Just the simple fact that Pennzoil Platinum 10w30 flows like a dino 5w30, is enough for me to use it in my truck (which calls for 5w30 year round) at least in the summer time since I drive very hard, and tow etc...the "stouter" 10w30 seems more logical to me. Better HTHS, and NOACK volitility numbers seem appealing to at least me. Chime in all! -Ponch
Viscosity question??
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The Amsoil 10W30/30 might be an option. I understand that it has no VI's.
Originally Posted By: Ponch
...at least in the summer time since I drive very hard, and tow etc...the "stouter" 10w30 seems more logical to me. Better HTHS, and NOACK volitility numbers seem appealing to at least me. Chime in all! -Ponch
You are exactly right, however, be forewarned, any gravitation toward anything thicker at all (even with good logic and reason) , will be met with shift and harsh condemnation. The thin police will get you, and you will be openly ridiculed for not using 0W-10 for towing in the summer.
...at least in the summer time since I drive very hard, and tow etc...the "stouter" 10w30 seems more logical to me. Better HTHS, and NOACK volitility numbers seem appealing to at least me. Chime in all! -Ponch
You are exactly right, however, be forewarned, any gravitation toward anything thicker at all (even with good logic and reason) , will be met with shift and harsh condemnation. The thin police will get you, and you will be openly ridiculed for not using 0W-10 for towing in the summer.
Originally Posted By: Ponch
from what I understand about oils is that whether dino or synthetic the manufacturer must add more viscosity improvers to get a larger viscosity spread to reach a 0w30 or 5w30. And these VI's actually break down with time, and cause oxidation, and thicken.
Yes and no.
One thing real quick: It's viscosity index improver, or VII. VI means viscosity index.
Some oils need fewer VIIs than others. Synthetics definitely need fewer VIIs than dino oils do. Some synthetics can achieve a 0w-30 rating without any VIIs. All oils today need fewer VIIs than their counterparts.
AFAIK, VIIs today are much more resistant to breakdown than they used to be. Some VIIs will survive almost any engine without breaking down.
Oils with higher viscosity indices will still have higher NOACK volatility numbers, but this is often because a base stock with a higher viscosity index almost always has higher volatility on its own.
Originally Posted By: Ponch
I see alot of uoa's with viscosity thickening slighlty after time, so your 5w30 after it thickens also effects your cold pumpability, not a 5w30 anymore, but maybe a 10w30 or even higher?
I don't think it's typical for a 5w30 thicken to that point.
Originally Posted By: Ponch
I am wondering if just running a 10w30 will not thicken as bad as a 5w30 or 0w30.
Probably. But then, it also probably starts out thicker, at least at low temps.
Originally Posted By: Ponch
I had thickening problems awhile back with Amsoil 0w30, and HDD 5w30, but never tried their 10w30.
Weren't the 0w-30 and HD 5w30 known for thickening at one time? They may have fixed that.
But either way, you're probably right that the 10w-30 will be more stable.
Originally Posted By: Ponch
Just the simple fact that Pennzoil Platinum 10w30 flows like a dino 5w30, is enough for me to use it in my truck (which calls for 5w30 year round) at least in the summer time since I drive very hard, and tow etc...the "stouter" 10w30 seems more logical to me.
Don't forget: cold pumpability is measured at different temps for 0w, 5w, and 10w. You might look at a 5w30 and a 10w-30 and see similar numbers, but the 5w30's numbers come from a lower temperature test. 5w usually still means better cold pumpability than 10w.
However, you're probably right that a good synthetic 10w-30 may be all you need. I wouldn't lose sleep over using it.
from what I understand about oils is that whether dino or synthetic the manufacturer must add more viscosity improvers to get a larger viscosity spread to reach a 0w30 or 5w30. And these VI's actually break down with time, and cause oxidation, and thicken.
Yes and no.
One thing real quick: It's viscosity index improver, or VII. VI means viscosity index.
Some oils need fewer VIIs than others. Synthetics definitely need fewer VIIs than dino oils do. Some synthetics can achieve a 0w-30 rating without any VIIs. All oils today need fewer VIIs than their counterparts.
AFAIK, VIIs today are much more resistant to breakdown than they used to be. Some VIIs will survive almost any engine without breaking down.
Oils with higher viscosity indices will still have higher NOACK volatility numbers, but this is often because a base stock with a higher viscosity index almost always has higher volatility on its own.
Originally Posted By: Ponch
I see alot of uoa's with viscosity thickening slighlty after time, so your 5w30 after it thickens also effects your cold pumpability, not a 5w30 anymore, but maybe a 10w30 or even higher?
I don't think it's typical for a 5w30 thicken to that point.
Originally Posted By: Ponch
I am wondering if just running a 10w30 will not thicken as bad as a 5w30 or 0w30.
Probably. But then, it also probably starts out thicker, at least at low temps.
Originally Posted By: Ponch
I had thickening problems awhile back with Amsoil 0w30, and HDD 5w30, but never tried their 10w30.
Weren't the 0w-30 and HD 5w30 known for thickening at one time? They may have fixed that.
But either way, you're probably right that the 10w-30 will be more stable.
Originally Posted By: Ponch
Just the simple fact that Pennzoil Platinum 10w30 flows like a dino 5w30, is enough for me to use it in my truck (which calls for 5w30 year round) at least in the summer time since I drive very hard, and tow etc...the "stouter" 10w30 seems more logical to me.
Don't forget: cold pumpability is measured at different temps for 0w, 5w, and 10w. You might look at a 5w30 and a 10w-30 and see similar numbers, but the 5w30's numbers come from a lower temperature test. 5w usually still means better cold pumpability than 10w.
However, you're probably right that a good synthetic 10w-30 may be all you need. I wouldn't lose sleep over using it.
Originally Posted By: gfh77665
Originally Posted By: Ponch
...at least in the summer time since I drive very hard, and tow etc...the "stouter" 10w30 seems more logical to me. Better HTHS, and NOACK volitility numbers seem appealing to at least me. Chime in all! -Ponch
You are exactly right, however, be forewarned, any gravitation toward anything thicker at all (even with good logic and reason) , will be met with shift and harsh condemnation. The thin police will get you, and you will be openly ridiculed for not using 0W-10 for towing in the summer.
No, he's not exactly right. He's right under the "conventional wisdom" umbrella, which I subscribe to myself, but that hardly makes him exactly right.
Here's the way I see it...
If he used a good synthetic 5w30 year around with reasonable OCIs, he would never have an oil related engine problem. Here's the kicker...The same thing can be said if he used a good synthetic 10W-30 oil. I'd use whichever oil made me sleep better.
Originally Posted By: Ponch
...at least in the summer time since I drive very hard, and tow etc...the "stouter" 10w30 seems more logical to me. Better HTHS, and NOACK volitility numbers seem appealing to at least me. Chime in all! -Ponch
You are exactly right, however, be forewarned, any gravitation toward anything thicker at all (even with good logic and reason) , will be met with shift and harsh condemnation. The thin police will get you, and you will be openly ridiculed for not using 0W-10 for towing in the summer.
No, he's not exactly right. He's right under the "conventional wisdom" umbrella, which I subscribe to myself, but that hardly makes him exactly right.
Here's the way I see it...
If he used a good synthetic 5w30 year around with reasonable OCIs, he would never have an oil related engine problem. Here's the kicker...The same thing can be said if he used a good synthetic 10W-30 oil. I'd use whichever oil made me sleep better.
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The thin police will get you, and you will be openly ridiculed for not using 0W-10 for towing in the summer.
You forgot to include, "through Death Valley in July ..flat out" ..but good enough, I suppose.
The thin police will get you, and you will be openly ridiculed for not using 0W-10 for towing in the summer.
You forgot to include, "through Death Valley in July ..flat out" ..but good enough, I suppose.
A 10w-xx will be "thicker" than a 5w-xx for most cold start situations, not because of the 10w appellation but because most common 10wXX have a higher 40c viscosity (say 80 v 65cSt) than a typ 5wXX.
ex: RT10w-30 has an calc/extrapolated viscosity in the low 300cSt whereas PYB5w30 is in the low 200cSt at 60 degrees F. As far as oxidative thickening, some PAO based oils show this more than others in the long term testing I've seen, and, would most likely be a concern in 'looser' engines running an extended OCi (1x/year). HTH.
ex: RT10w-30 has an calc/extrapolated viscosity in the low 300cSt whereas PYB5w30 is in the low 200cSt at 60 degrees F. As far as oxidative thickening, some PAO based oils show this more than others in the long term testing I've seen, and, would most likely be a concern in 'looser' engines running an extended OCi (1x/year). HTH.
My past knowledge was VII are required in 5w30 PAO synthetics, so they would surely be required in 0w-30. Now a 5w-20, likely not.
The problem is, too me anyway, is you dont know what quality of basestock the blender used for each grade. They are not required to use the same thing. my point is say you wanted to make a really good 5w30 so you use a top of the line gr2 basestock with a viscosity index of 115 and add some VII to get to whatever 100C viscisity you are targeting. Now to make a 10w30 you could choose a lower quality basestock, still grp2 but maybe has a viscosity index of 95. Now you add the same amount of VII(hypothetically) to bring 100C viscosity to some target that falls in the w30 range. Now the 10w30 has worse cold weather flow, and lower quality basestocks will little advantage. This is not always the case and if basestocks were equal, i would probably agree with what you said above and choose the 10w30 because it flows fine for my temps. Im sure i missed something but just wanted to make a point that 10w30 may not always be better than 5w30.
I think your logic makes sense. If you look at Pennzoil Platinum, their 10w30 looks like a 5w30 on paper, with the added benefit of having better CCS numbers at -30 than 5w30 dino Pennzoil.
10w30 may stand up to fuel dillution slightly better than a 5w30 would, since it has a little more wiggle room.
Having said all that, i've also been impressed by the spec numbers of the new mobil1 AFE 0w30.
10w30 may stand up to fuel dillution slightly better than a 5w30 would, since it has a little more wiggle room.
Having said all that, i've also been impressed by the spec numbers of the new mobil1 AFE 0w30.
"thin police" LOL!
dnewton3
Staff member
Oooooh - wait a minute ...
why not blend them, netting a 7.5w30 for year round use ...
Seriously, though, I doubt it makes much (if any) difference at all to the engine. To really know, with unequivical proof, you'd have to do so many UOAs and subsequent teardown analysis that your budget and calendar would never recover.
why not blend them, netting a 7.5w30 for year round use ...
Seriously, though, I doubt it makes much (if any) difference at all to the engine. To really know, with unequivical proof, you'd have to do so many UOAs and subsequent teardown analysis that your budget and calendar would never recover.
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Originally Posted By: jstutz
The problem is, too me anyway, is you dont know what quality of basestock the blender used for each grade. ... ... but just wanted to make a point that 10w30 may not always be better than 5w30.
I was talking synthetic so mainly 85/15% group iv-v basestock. I agree on dino you can get some crud 10w-30 - and it would prob work fine in non stressd apps. A proper syn 10w-30 will have NO vii. The M1 AFE surely has vii. May make a diff in aircraft or offshore boat running near wot at max torque.
The problem is, too me anyway, is you dont know what quality of basestock the blender used for each grade. ... ... but just wanted to make a point that 10w30 may not always be better than 5w30.
I was talking synthetic so mainly 85/15% group iv-v basestock. I agree on dino you can get some crud 10w-30 - and it would prob work fine in non stressd apps. A proper syn 10w-30 will have NO vii. The M1 AFE surely has vii. May make a diff in aircraft or offshore boat running near wot at max torque.
Engine oils tend to thin a bit after 3k or so, then only thicken when old and beat up.
I don't think VII problems are a deep concern, nowadays.
I'm sure there are oils there that are weak in this area, but I don't give common name brands a second thought about this for normal use.
Since engines run OK on such a wide variety of oils , many will chime in to say how they used X or Y as proof of their being better. So take it with a grain of salt.
I don't think VII problems are a deep concern, nowadays.
I'm sure there are oils there that are weak in this area, but I don't give common name brands a second thought about this for normal use.
Since engines run OK on such a wide variety of oils , many will chime in to say how they used X or Y as proof of their being better. So take it with a grain of salt.
Well it could still be the same argument right? Meaning Pure group 3 basestock with vi of 121 made into 10w30 or one that is blended PAO with vi of 140 made into upper limit 5w30. Splitting hairs here but still one can not assume the 10w30 will be better all the time. Im definitely not trying to be argumentative but this is kind of confusing too me. It would be so much easier if oil companies would just let you know that the heck your buying.
Originally Posted By: mechtech2
I don't think VII problems are a deep concern, nowadays.
I'm sure there are oils there that are weak in this area, but I don't give common name brands a second thought about this for normal use.
Since engines run OK on such a wide variety of oils , many will chime in to say how they used X or Y as proof of their being better. So take it with a grain of salt.
Yea, i think we would all agree that VII are very good today and that were probably arguing semantics. Im just not convinced a 10w30 will be heavier duty or whatever than a 5w30 unless you really know it is made of the same material. It would make the manufacture lots of money to produce a lower grade 10w30 because its fairly easy to make now a days.
I don't think VII problems are a deep concern, nowadays.
I'm sure there are oils there that are weak in this area, but I don't give common name brands a second thought about this for normal use.
Since engines run OK on such a wide variety of oils , many will chime in to say how they used X or Y as proof of their being better. So take it with a grain of salt.
Yea, i think we would all agree that VII are very good today and that were probably arguing semantics. Im just not convinced a 10w30 will be heavier duty or whatever than a 5w30 unless you really know it is made of the same material. It would make the manufacture lots of money to produce a lower grade 10w30 because its fairly easy to make now a days.
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