Why not a 0w all the time?

[cnl64590]

Well, I must admit I have been reading bitog for a few years now. I must adnit I love the site and all the info. So thank you. After reading that oil viscosity article a few times, I came up with this perhaps naive question: Why would the averae syn user ever not use a 0wXX oil? Since all oil is too thick on startup, wouldn't one want to achieve the proper viscosity as soon as possible? sorry for the rant!! Thanks for your knowledge

 

[HyundaiGuy]

I've only been here a short time, but learn something new here all the time. Your idea is exactly what I am thinking, I've switched both of our cars to 0W20 and plan to run it year round.

 

[ahoier]

Some cars are actually specing 0w oils "year round" think the Prius and Civics? Could be wrong though......but yea, I too wonder the same thing, I'd think the best bet for protection would be the lowest weight possible, to get the oil flowing at cold start, the fastest - which should be accomplished with a zero-weight oil...?

 

[spasm3]

i've always wondered what temperature it took to see the diff in a 0w and say a 5w

 

[Shannow]

To get wide spreads, traditionally viscosity index improvers are used, often, even in expensive synthetics. In my climate, where it doesn't get below around -10C with any regularity, more commonly -5to-7, I'd rather use Amsoil's "straight" 30/10W-30, than a 0W-40.

 

[Lead Shoes]

Because of the viscosity improvers added in to make it a 0w in the cold, and 30weight at high temp, it causes more shearing, which is a bad thing, AFAIK.

 

[DragRace]

There is nothing wrong with running 0WXX all year round in hot or in cold climates. Don't let the 0 fool you. Sure it does flow better when it is cold but it is still a 20 or 30 weight oil and will protect you as such when the engine gets hot. My last run of 0w30 Red line,I ran for 11 months,had no issues.As for this winter fill,I'll be running Amsoil's 0w30,and from that point on,I'll be sticking with a 0w30. Dont be afraid of the 0-weight oils.

 

[MrRPM]

my plan is to run M1 0w-40 in my jeep, i read those articles and also thought the same...

 

[Shannow]

Originally Posted By: DragRace

There is nothing wrong with running 0WXX all year round in hot or in cold climates. Don't let the 0 fool you. Sure it does flow better when it is cold but it is still a 20 or 30 weight oil and will protect you as such when the engine gets hot. My last run of 0w30 Red line,I ran for 11 months,had no issues.As for this winter fill,I'll be running Amsoil's 0w30,and from that point on,I'll be sticking with a 0w30. Dont be afraid of the 0-weight oils.

You are right of course, as long as what's giving the high viscosity index doesn't negatively impact the HTHS. I'd rather that oils were rated on some cold performance parameter and HTHS rather than the existing bracketted arbitrary system.

 

[4x4chevydude]

THere is nothing wrong with it at all and I am sure alot of poeple do run it all year long especially in temprate climates...I would say even very hot climates it is still ok but may want to do a 0w30 instead of a 20 in those situations

 

[ARCOgraphite]

This is all about the viscometrics and pumpability of the basestock at -40degC/F not it being a "zero weight oil" An ACEA A3B4 oil could meet the 0-winter rating and be thicker at all reasonable starting and running temps over a ILSAC GF5. That said I would love a well designed engine that runs on a 0w20 and that 0w20 is shear stable an nearly devoid of viscosity index improvers. VI are not lubricants and can sludge and shear. Measure your cheap walmart sourced 0w20 joke synthetic with 3000 miles on the oil and see if it still meets a new cold pumpability target. It wont.

 

[bruno]

I've been running 0W-40 for a long time now , all year every year . Temperatures here in NJ can go as low as 0F and as high as 100f .

 

[CATERHAM]

Originally Posted By: ARCOgraphite

Measure your cheap walmart sourced 0w20 joke synthetic with 3000 miles on the oil and see if it still meets a new cold pumpability target. It wont.

Really, and I presume you've done this? And name a "cheap 0W-20" sold by Walmart? Even the ultra high 200+ VI 0W-20's developed by the Japanese OEM's have proven to be quite shear stable.

 

[mechtech2]

Sure, it's a great idea. But any 0-xx is expensive. Since regular dino is just fine for many scenarios, there is no actual need for the 0.

 

[spasm3]

Is there any difference in the cold viscosity of a 0w and a 5w from 0 degrees f and up? I'm curious if anyone knows how cold it would need to be to see a diff in 0 and 5 w rated oils.

 

[45ACP]

You could probably use Redline 0W-20, in any 5W-30 app. It is a "thick" 20, and AFAIK it uses NO VIIs. Im thinking of using it (RL 0W-20) in my 91 CRX Si, instead of off-the-shelf Castrol Edge 5W-30. And yeah it gets hot down here, but... given that it is a "thick" 20, i should be Ok even driving all day with it. CATERHAM, yes? No? You are the expert i defer to in these logic tests of mine, with the oil.

 

[LeakySeals]

Originally Posted By: spasm3

Is there any difference in the cold viscosity of a 0w and a 5w from 0 degrees f and up? I'm curious if anyone knows how cold it would need to be to see a diff in 0 and 5 w rated oils.

Good question! And oils with wide ranges like 0w-40. What happens when the additives that create that range begin to wear off. Does the oil start getting thinner or thicker?

 

[4x4chevydude]

Originally Posted By: ARCOgraphite Measure your cheap walmart sourced 0w20 joke synthetic with 3000 miles on the oil and see if it still meets a new cold pumpability target. It wont. The cheeap wal-mart 0w20 if they even make a 0w20 supertech will be just as good as most other 0w20 out there as ling as it meets the stadnards that your car specs...the reason its cheap is becuase of advertising and gimmiks...i just made a whole post about this if you search supertech...dont believe its lower quality oil

 

[45ACP]

I have not seen a 0W-20 Supertech. It would be XOM if it was. ST is good oil. No conventional 0W-20s, either.. only 5W-20. Wondering what CATERHAM thinks of my observation.

 

[redwolf4k]

I would rather present the question the other way around: If you live in a climate that doesn't ever see temps below 0 degrees F why would you want to run a 0w oil? Some of these thinner winter rated oil causes some of my engines to chatter at the top end when cold. I see no benefit to go below a 10w or 5w oil in most areas in the US. The oil is all around thinner through the ambient temperature range, right? Sure, you dont ever want to run a 20w50 oil in the winter, but I cant see the benefit of 0w over 5w, and sometimes even over 10w. Ive seen the same engine through the generation of a specific car go from 10w30 recommended, to 5w30, to 0w20, etc. Same exact engine. I think it is sort of a joke.