Light-weight oils - which is thicker 5W30 or 0W40?

[testerdahl]

I'm confused. I did a video talking about a theory on light-weight oils and their impact on reliability with regards to engine debris.

My confusion in on light-weight oils. I swear I had it in my head that the new 0W40 was a thinner oil that EVERYONE was bitching about. I've had person after person bitch about it and say they want to return to the "thicker" 5W30.

So, I do a video showing the GMC Canyon with the 5W30 vs the Ram Hurricane with 0W40 and claim the Hurricane has the thinner oil.

Drive to Denver, get the hotel and check the comments. Get destroyed in the comments for making this rookie mistake. WTF?

I Google it and people are arguing about it. Turns out, when it is cold 5W30 is thicker and when it is hot 0W40 is thicker.

But, hold on a minute, what about the people who want to return to the "thicker" 5W30 oil? Are those people actually wrong?

Or are those people upset about something I'm clearly missing??

Took the video down. I get enough hate as it is and don't need more. Just confused AF with the internet.

 

[Brado]

Funny enough I was just wondering about this today since I'm coming up on my first oil change. I'm interested to see what others have to say about this. For the most part, I'll probably just stick with manufacture suggestions. But if I see some solid proof to sway me, I'm game to consider it.

 

[Fightnfire]

In winter at cold temperatures the 5W30 is thicker on start. Once the engine is up to operating temperature the 0w-40 is thicker.

I watched a little bit of that video, I thought you were talking about 0W20 because that's what they use in the standard output and 0W40 in the high output.

That's the way I've always understood it. The first number is viscosity or thickness at cold temperature the second is thickness at operating or hot temperature.

 

[Saddle Tramp]

I don't blame you for taking it down. I'm confused too. We have some mowers at work that have the same engines as the Mules. Exact same. Now get this; the engines in the mowers were blowing up using the same oil as the engines in the mules. Kawasaki did a recall and ordered that the engines in the mowers use 20 W 40 instead of 10 W 30 because of the higher revs and longer duration at these revs on the mower.

What really confuses me about the truck oil issue is the fact that once the oil hits it's proper "Warm" temperature, it doesn't have the viscosity to clear the debris out. Why does 5 work better cold than 40 does warm?

 

[testerdahl]

I think my lesson here is to slow down, let the team do their thing and triple check things. I could have easily avoided this F up.

 

[Link550]

Id love to know how the manufacturers decide on a oil spec. Evidently the HO needs heavy oil and the SO can use thin. The same was true of the run of the mil 5.7 vs high performance hemis. I'm sure it's something to do with bearing load vs surface area. I wonder if the ho and so use the same bearings?

On the high production fleet engines I can see the reason for thin oil for emissions and fuel economy.

Anyways I'm rambling.

Don't feel bad about the oil spec stuff with the way media is today something will come up and everyone will forget about it.

 

[testerdahl]

Id love to know how the manufacturers decide on a oil spec. Evidently the HO needs heavy oil and the SO can use thin. The same was true of the run of the mil 5.7 vs high performance hemis. I'm sure it's something to do with bearing load vs surface area. I wonder if the ho and so use the same bearings?

I remember asking that question of the engineer in the interview I posted last year. IIRC - it has to do the hotter temps and customer use case for the HO Hurricane. They felt like the higher HP/Torque plus how the customer was going to drive trucks like the RHO meant it was better to have the heavier oil.

 

[Dusdaddy]

In winter at cold temperatures the 5W30 is thicker on start. Once the engine is up to operating temperature the 0w-40 is thicker.

I watched a little bit of that video, I thought you were talking about 0W20 because that's what they use in the standard output and 0W40 in the high output.

That's the way I've always understood it. The first number is viscosity or thickness at cold temperature the second is thickness at operating or hot temperature.

Makes perfect sense.
5w used to be the oil of choice in the winter over 10w. Still is for smaller stuff like ATVs. Many manufacturers of those rate 10w is good down to 0F, 5w if you go below 0F and 0w is the best.

What will really blow your mind, is that the 5w means something completely different than the 30 that follows it. You have Centistokes, Centipoise and the all-important Hight Temp High Shear number. It all comes down to the SAE J300 chart. The Oil Geek did a video some time ago about it.