Why not 0W-50 for all?

[ShawnTRD]

It's not all about cold start. I'm more worried about how well my car is protected at 200f+ when running 2000+ RPM. Why has 0W50 or 5W50 not become a thing? Is 0W50 that much thinker at 200f? Most cars call for 5W20 or 5W30 here.

 

[CT8]

The wider the viscosity spread the thinner the oil is between the oil shearing parts in the engine

 

[widman]

It is too viscous at operating temperatures, reducing performance, lubrication, mileage, etc. Viscosity is the measure of resistance to flow. Don't need more resistance.

 

[skyactiv]

When is the last time you wore out an engine and the rings and bearings needed replaced?

 

[1JZ_E46]

There's no such thing as a free lunch. There are many drawbacks when trying achieve too many use cases (i.e. wide viscosity range) with a single oil. Just like an all season "snow" rated tire will be mediocre at everything instead of great at certain tasks.

 

[zrxkawboy]

Most engines don't need anywhere near a 50 wt at operating temps.

 

[maxdustington]

Originally Posted by 1JZ_E46

There's no such thing as a free lunch. There are many drawbacks when trying achieve too many use cases (i.e. wide viscosity range) with a single oil. Just like an all season "snow" rated tire will be mediocre at everything instead of great at certain tasks.

I'm not so sure about that. I would consider a euro 0W40 an oil that is hard to go wrong with in 90% of applications.

 

[d00df00d]

Engine oil should be as thin as possible, and as thick as necessary. Thin to minimize drag and heat in the bearings. Thick to maintain the necessary oil film.

 

[ZZman]

With tighter tolerances in engines today and water cooled systems, 50w is too thick and not needed.

 

[tig1]

Originally Posted by ZZman

With tighter tolerances in engines today and water cooled systems, 50w is too thick and not needed.

Don't believe that the thicker the oil the better. Use what the engine builder recommends.

 

[bullwinkle]

In a 0W20 specced engine, especially with a timing chain & oil operated variable valve timing-the 50 weight wouldn't stay a 50 for long, it would start shearing. Plus there would be MPG & power losses.

 

[StevieC]

Originally Posted by ShawnTRD

It's not all about cold start. I'm more worried about how well my car is protected at 200f+ when running 2000+ RPM. Why has 0W50 or 5W50 not become a thing? Is 0W50 that much thinker at 200f? Most cars call for 5W20 or 5W30 here.

I operate my vehicles like fleet because they are running all day long for my job. I ran 5w20 in my Dodge Journey 2.4 Cylinder. It's a high revving engine that was formely rated for 5w30. I had 0 issues and my wear numbers after a 9,000 mile run were 4ppm on the Iron and 0's on all the other metals with a TBN of 6+ and a non-existent TAN. I have 0 issues running an oil that thin on the highway or stop-go traffic for prolonged periods of time in the middle of the summer heat waves. Thick is over rated. It does have it's place in certain applications but otherwise there is no need for it. Run different weights and do some UOA's and decide for yourself.

 

[SilverSnake]

Was the specified oil for my 2012 Shelby GT 500. Worked great: https://parts.ford.com/shop/en/us/synthetic-oils/oil-engine-6610221-1

 

[addyguy]

This was exactly the thinking in the early 1970's, when the 10W-50 viscosity came out. Shell was first with X-100 10W-50; then everyone followed suite. There is a popular science or popular mechanics article on the new 10W-50's; google 'Maxi oils' and you will find it.

 

[BrocLuno]

There are plenty of 15W-50's out there. Since 15W is good to well below 0*F, why look for a 0W ... 99% of folks in the lower 48 will never need a 0W. And if they do, the engine in the Prius won't want a 50 at op temp ... Any engine that needs a 50 at op temp (mod'd BBC, air-cooled Porsche, many track rated Fords, etc.) will never be driven in the freezing conditions that would need a 0W ...

 

[jongies3]

Unless you're running an air cooled v-twin motorcycle or old VW Bug in hot weather and traffic, a 50wt isn't necessary for a liquid cooled car engine, they'll never get hot enough to need the extra protection from thermal breakdown. 30wt is the universal average and most widely used viscosity to date for good reason, it offers good protection across a range of temperatures and is easy to come by. Try finding a 5W-50 at any parts store!

 

[DS9]

Why not football boots for every sport?

 

[Nick1994]

Read this first https://www.bobistheoilguy.com/motor-oil-101/

 

[FCD]

Yeah, for engiens that want a 50 at operating temp, in above freezing temps, can use a 15W-50 or 20W-50 just fine.

 

[FCD]

Originally Posted by jongies3

Unless you're running an air cooled v-twin motorcycle or old VW Bug in hot weather and traffic, a 50wt isn't necessary for a liquid cooled car engine, they'll never get hot enough to need the extra protection from thermal breakdown. 30wt is the universal average and most widely used viscosity to date for good reason, it offers good protection across a range of temperatures and is easy to come by. Try finding a 5W-50 at any parts store!

Many older italian, British engines prefer a 50 at operating temp, which are not air cooled, and specify 50 grades from the factory. During the 60s and 70s, it was 20W-50 for almost everything in Europe. These engine many times do fine on a modern 15W-40 HDEO but love 20W-50 too.