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

[Pablo]

As long as he eliminated or accounted for every variable except the oil grade then he’s good.

Ok let's use the vis extremes and cocktail napkin........

21.9 cSt down to 12.5 cSt @ 100°C

Air cooled. Has to be.

Relatively cool day.

Maybe a couple degree F. Not 10°F - not repeatably.

Are we talking actual oil sump temperature or case temperature?

 

[FTTSHO]

I do notice higher oil and coolant temps with thicker oils in certain engines. Specifically higher coolant temps on my father’s 2018 ND Miata, with the 2.0 skyactive, I always put in Valvoline advanced 0w20 at every oil change for him. One day we tried using some Valvoline advanced 5w30 just to try it out. We used it in the summer, thinking it would be better for the hot summer months, which it really isn’t, because main bearing clearances are 0.0007-0.0015.

Cars got 55,000miles now. Tried running 5w30 at 40,000 miles for 5k miles until we hit 45,000 miles.

Coolant gauge display is on a screen in the gauge cluster. With 0w20, the screen needle always sits below 210, probably more like 195-200 even in stop and go traffic in the hottest days in South Carolina. With 5w30, we noticed the needle staying at 210 in city driving, and very slightly higher than 210 in stop and go traffic. This never happens with 0w20. It always sits below 210, probably 195-200, even in stop and go traffic in hot South Carolina.

This was consistent during the 5k miles of 5w30 use. Then we switched back to 0w20, and the coolant gauge needle never ever touches 210.

Based on the skyactive 2.0’s factory main bearing clearance of 0.0007-0.0015, 0w20 should be more than adequate for daily driving for this particular engine especially with oil pressures that are on the high side compared to many other modern engines that run lower oil pressures during idle.

 

[Titan]

Coolant gauge display is on a screen in the gauge cluster. With 0w20, the screen needle always sits below 210, probably more like 195-200 even in stop and go traffic in the hottest days in South Carolina. With 5w30, we noticed the needle staying at 210 in city driving, and very slightly higher than 210 in stop and go traffic. This never happens with 0w20. It always sits below 210, probably 195-200, even in stop and go traffic in hot South Carolina.

If you were measuring oil temp, you would have a better case. Coolant temp is more a function of the thermostat setting and effectiveness of the radiator/fan system.

 

[Gladiator007]

This has been circulating over the internet. The guy claims to be one of the engineers that worked on the 3.6. Thicker oil does cause more wear in the valvetrain according to him.

Cropped from the thread here on Bob.

 

[Pablo]

This has been circulating over the internet. The guy claims to be one of the engineers that worked on the 3.6. Thicker oil does cause more wear in the valvetrain according to him.

Cropped from the thread here on Bob.

View attachment 291170

Do you have a link to this thread?

 

[Gladiator007]

Do you have a link to this thread?

Something to note is that this 3.6 got there on 5w-20

Thread '626,000 mile Pentastar teardown'

Jul 10, 2020

https://www.thedrive.com/news/34672...ysler-pentastar-v6-is-after-626000-miles

Looks like the internals were in good shape except for the timing chains and tensioners. My question is would these timing chains have lasted longer with thicker oils?

• wwillson
• Replies: 92
• Forum: Mechanical/Maintenance Forum

• 

 

[Glenda W.]

This has been circulating over the internet. The guy claims to be one of the engineers that worked on the 3.6. Thicker oil does cause more wear in the valvetrain according to him.

Cropped from the thread here on Bob.

View attachment 291170

The Pentastar was originally spec’d with 5W-30, then 5W-20, and finally 0W-20. @OIL_UDDER never did give details if this was 0W vs 5W. The Pentastar has no ADBV so dry starts after sitting are common. I chose a 0W-30 for good cold start pumpability and better high temp viscosity. Best of both worlds.

 

[ltslimjim]

The Pentastar was originally spec’d with 5W-30, then 5W-20, and finally 0W-20. @OIL_UDDER never did give details if this was 0W vs 5W. The Pentastar has no ADBV so dry starts after sitting are common. I chose a 0W-30 for good cold start pumpability and better high temp viscosity. Best of both worlds.

It would appear that the dry start condition could potentially be improved with said better pumpability. A 0w-30 with very good base oils could do this better than a low end 5w-20. So, not necessarily a “20 vs 30”difference in of itself.

 

[ka9mnx]

WOW

This has been circulating over the internet. The guy claims to be one of the engineers that worked on the 3.6. Thicker oil does cause more wear in the valvetrain according to him.

Cropped from the thread here on Bob.

View attachment 291170

WOW! I'm going to check my head bearings.

 

[Pablo]

The Pentastar was originally spec’d with 5W-30, then 5W-20, and finally 0W-20. @OIL_UDDER never did give details if this was 0W vs 5W. The Pentastar has no ADBV so dry starts after sitting are common. I chose a 0W-30 for good cold start pumpability and better high temp viscosity. Best of both worlds.

That's the problem. More precision needed, not just SAE ranges. What was the actual oil viscosity at start ups?

 

[kschachn]

It would appear that the dry start condition could potentially be improved with said better pumpability. A 0w-30 with very good base oils could do this better than a low end 5w-20. So, not necessarily a “20 vs 30”difference in of itself.

Sort of, maybe. Pumpability is really a binary, it will either pump or it won't. As long as the oil will flow to the pump pickup it will pump. Horsepower requirement will increase but it will pump.

And really the viscosity differences between a 0W winter rated oil and one with a 5W is only significant below about -30. Above that an oil with a 0W rating may or may not be thinner than one with a 5W rating even of a different grade. It's completely dependent on temperature.

 

[ltslimjim]

Sort of, maybe. Pumpability is really a binary, it will either pump or it won't. As long as the oil will flow to the pump pickup it will pump. Horsepower requirement will increase but it will pump.

And really the viscosity differences between a 0W winter rated oil and one with a 5W is only significant below about -30. Above that an oil with a 0W rating may or may not be thinner than one with a 5W rating even of a different grade. It's completely dependent on temperature.

Of course, good points.

My comment was meant to be in the context of an apparently fully drained down top end overnight; due to no ADBV perhaps leading to more dry starts. I could have it conceptualized wrong, just seeing if there were a way to validate the comments of the tech believing it were the oil. Might not be a real thing, as it’s still anecdotal.

 

[Gladiator007]

It would appear that the dry start condition could potentially be improved with said better pumpability. A 0w-30 with very good base oils could do this better than a low end 5w-20. So, not necessarily a “20 vs 30”difference in of itself.

Hopefully, I assume Amsoil 0w-30 flows better than some cheap off-the-shelf oil. It's hard to find a bad zero 0w-30 though.

 

[ltslimjim]

Hopefully, I assume Amsoil 0w-30 flows better than some cheap off-the-shelf oil. It's hard to find a bad zero 0w-30 though.

Their 0w-30 is rated almost as good as their 0w-20; per ASTM D5293 at -35C

https://amsoilcontent.com/ams/lit/databulletins/g2880.pdf

So, yes, it has pretty good “pumpability”; technically not “flow” down to that temp.

And that’s to the points other members above such as @kschachn and @Pablo indicated…when we’re not in sub-freezing temps it may not even matter or be proven to be relevant.

 

[kschachn]

Hopefully, I assume Amsoil 0w-30 flows better than some cheap off-the-shelf oil. It's hard to find a bad zero 0w-30 though.

It will flow like an oil with a 0W winter rating. Which as I noted isn’t relevant unless you’re below about -30 or so.

If the “cheap off-the-shelf oil” also has a 0W winter rating then it’s also guaranteed to flow as it needs to do to earn that rating. Like Mobil 1 0W-40 cheap and off the shelf at Walmart.

 

[Gladiator007]

This engineer ran 5w-20 in the winter and 5w-30 in the summer in his 3.6. That's what I'm going to do, signature series 20 in the winter and 30 in the summer