Switching from 0w-20 to 0w-30 experience

[dbias]

I’ve been running ESP 0w-30 in my 2023 Grand Cherokee since after the first “free” dealership oil change at 5k miles. This gives extra protection for the 3.6 and puts it on the same oil as the GTI so it simplifies the oil stash.
So I’ve put both the 3.6 and the EA888 engines on 0w-30 instead of 0w-20 and have no concerns about it. Both engines are decades old designs and were spec for heavier oil in the past.
I did the same for my 2015 JGC which my son now has with 125k trouble free miles on it.

 

[Glenda W.]

Thanks!, has your experience been similar?

Less valvetrain noise for sure. I didn’t even keep 0W-20 in long enough to check fuel economy.

 

[Hohn]

I'm not sure exactly what a "dry start" is in the context of an engine continually bathed in lube oil, but I don't think it's a thing. Excessive oil pressure delay? Sure. Low pressure once the oil arrives? Also possible. But short of draining all the oil or freezing it into a solid block at -80F, there's no "dry start" issue on any mass produced automotive engine.

If you need more film thickness on the Pentastar, the solution is a premium no-VII oil like HPL No VII 5w30. Because these oils have no VII, they do not lose apparent viscosity with shear rate.

Remember-- much of the research in modern API oils is trying to get them to do the opposite-- to behave at faster shear rates as if they are a LIGHTER oil, because this is where the primary fuel economy benefits originate. This causes a 30 grade to behave more like a 20 grade under higher shear rates. Think of it as pushing HTHS lower for a given KV100. This is the opposite of what we want for film thickness.


A Euro 0w-30 generally will have a higher HTHS of 3.5 minimum (to meet Euro specs). So while API oils are trying to push HTHS lower and lower within grade, the Euro oil will have a stouter HTHS within grade.

Thus, the reason to prefer a 0w-30 has nothing to do with "needing" the 0w for cold weather and everything to do with how the oil performs when warm.

 

[MuzzleFlash40]

I'm not sure exactly what a "dry start" is in the context of an engine continually bathed in lube oil, but I don't think it's a thing. Excessive oil pressure delay? Sure. Low pressure once the oil arrives? Also possible. But short of draining all the oil or freezing it into a solid block at -80F, there's no "dry start" issue on any mass produced automotive engine.

What I was referring to is the design of the cartridge oil filter housing and cooler combo that sits on top of the engine. The design lacks an anti-drain back valve so much of the oil drains back into the pan.

It’s a debate on how serious it actually is (if at all) but it’s something that I was wanting to take into consideration.

 

[PandaBear]

Not sure about your engine specifically but I remember some research / marketing document that said 5w20 vs 5w30 and 5w30 vs 10w30 is about 1.5% mpg difference MAX in the lab. I would imagine real world difference would likely be even less than that since engine are even less likely to operate in ideal environment in real world than in the lab.

 

[Hohn]

What I was referring to is the design of the cartridge oil filter housing and cooler combo that sits on top of the engine. The design lacks an anti-drain back valve so much of the oil drains back into the pan.

It’s a debate on how serious it actually is (if at all) but it’s something that I was wanting to take into consideration.

So oil pressure delay, perhaps.

My understanding is that the design of their canister mostly traps oil in it, only allowing drainback when the cap is unscrewed as if to service the element.

Drainback is not a big deal by itself. What matters is the total volume the oil pump must fill from a start or restart. The filter is part of that, but it's only part. If the oil pump is somewhat oversized and the rest of the oil system quite efficient, you can get oil pressure in < 2 seconds with no oil in the filter at all.

 

[Titan]

Not sure about your engine specifically but I remember some research / marketing document that said 5w20 vs 5w30 and 5w30 vs 10w30 is about 1.5% mpg difference MAX in the lab. I would imagine real world difference would likely be even less than that since engine are even less likely to operate in ideal environment in real world than in the lab.

I drained the factory fill from my 300+ HP Lexus V6 with just a few hundred miles on it. Put in Mobil ESP 0w30. Just drove a 500 mile round-trip at mostly 75-80 mph, with the typical stop-and-go Atlanta traffic. Two adults in the vehicle. Averaged 34 mpg (hand calculated). Don't know what mpg that would provide with 0w20, and I'm not going to find out...34 mpg is good enough for me.

 

[Gladiator007]

I have two concerns. First, 0w-30 increases oil temperature and what harm could that extra heat do in the long term given that there is so much plastic around this motor? Secondly, the new 3.6 has an entirely new valvetrain for 0w-20. How to test specifically for valvetrain wear in case 0w-30 does cause abnormal valvetrain wear?

 

[Glenda W.]

I have two concerns. First, 0w-30 increases oil temperature and what harm could that extra heat do in the long term given that there is so much plastic around this motor? Secondly, the new 3.6 has an entirely new valvetrain for 0w-20. How to test specifically for valvetrain wear in case 0w-30 does cause abnormal valvetrain wear?

Remember oil temperature has more effect on viscosity than what’s printed on the bottle. Meaning a 20 grade ran in cold climates is thicker than a 30 grade ran in hot climates. Engines are designed to operate in a wide range of viscosities. If they weren’t we’d have big problems. My Jeeps oil temps around town are around 200, offroad 240.

 

[kschachn]

I have two concerns. First, 0w-30 increases oil temperature and what harm could that extra heat do in the long term given that there is so much plastic around this motor? Secondly, the new 3.6 has an entirely new valvetrain for 0w-20. How to test specifically for valvetrain wear in case 0w-30 does cause abnormal valvetrain wear?

The truly tiny increase in film temperature is irrelevant and inconsequential.

And a higher HT/HS decreases wear, not increases it. Your concerns are phantom ones without technical basis.

 

[rstcso]

I have two concerns. First, 0w-30 increases oil temperature and what harm could that extra heat do in the long term given that there is so much plastic around this motor? Secondly, the new 3.6 has an entirely new valvetrain for 0w-20. How to test specifically for valvetrain wear in case 0w-30 does cause abnormal valvetrain wear?

As @Glenda W. said, viscosity is a range. In the case of HPL's Premium Plus PCMO, their 0W-20 viscocity is close to the upper end of a 20 @100C while their 0W-30 is closer to the lower range for 30 @100C. The HT/HS difference is less than 0.3. However, not all oils are created equal and I expect both of these to stay well within range for each during a drain interval.

I'd be surprised if these two oils ran measurable temperature differences from each other.

As for how to measure valve train wear, start with a virgin sample of the oil you plan on running, then start UOA testing. Over the course of many samples, using trend analysis, you'll learn what looks "normal" for that oil in your engine. Should something begin having excessive wear, the UOAs may help catch it.