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Changing oil weight

Heimkehr

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So I’ve read a few things about swapping from 0w-20 to something a little thicker in the 3.6L. I’m due for an oil change and was wondering if I should swap to a 5w and if now is a good time with winter almost here. We live in TN so winter isn’t too harsh but it can get to the double and single digits occasionally. I’m at 58k miles on my stock 21 JLUR.

Any advice is appreciated!
This isn't an apples-to-apples comparison, but...

One of my motorcycles requires a thinner oil whenever the mercury is consistently below 50°F. From experience, using the heavier Summer oil makes for hard starting, so having two published oil specifications for the engine makes sense.

It's doubtful that pivoting from a 0W to a 5W would have any noticeable effect on the starting or running quality of the Pentastar, though. šŸ‘
 

iklo

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I keep records of everything. When I bought my BMW F10 in 2014, the shtick was to use the Castrol 5W30. It said so in on the metal plate epoxied to the engine block.

By the time the first oil change was due, BMW switched suppliers and the oil grade. It became Shell and 0W30. The same N55 motor. No reason other than climate change and EU a**holes. Anyways, at some point the message in the instrument cluster will will pop up: "Oil at the min level. Add 1Qt ASAP".

With BMW things sometimes are not that complicated. You can add any oil as long as it is on the approved list. LL-01 in my case. I kept experimenting as the chart below illustrates.

My educated guess is that in the long run none of this matters. As long as you change oil at all: That one significant dip at 124529 miles at the middle of the chart was when the dealer just reset the oil change indicator, but forgot to actually change the oil. Oops.

Jeep Wrangler JL Changing oil weight 1765403558054-jd
 
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WillysMeow

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@Odyssey USA Lower piston ring tension is an attempt at increasing mpg and cafe numbers, sometimes with increased oil consumption (Subaru LOL), and increased blow by from lower ring tension can dirty oil quicker.
 

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Pape

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So you're intentionally moving your Hersey number to the right on the Stribek curve, most likely to the point where you're just increasing friction with no wear benefit?

I have no idea why you're mentioning the oil that happens to be used by a specific Mercedes. Are you thinking your v6 is somehow engineered with the same characteristics?
Actually there is a good chance it does as during the design phase Mercedes and Chrysler where room mate :LOL:
 

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Actually there is a good chance it does as during the design phase Mercedes and Chrysler where room mate :LOL:
That ended years before either engine was introduced, but yeah, they're very, very similar! I hear about people swapping Pentastars into their G-Wagons all the time! Lots of people say they feel like a rocket ship!
 

Pape

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That ended years before either engine was introduced, but yeah, they're very, very similar! I hear about people swapping Pentastars into their G-Wagons all the time! Lots of people say they feel like a rocket ship!
well first pentastar was released in 2010 and Mercedes and Chrysler parted way in 2007. I Recon it take way more than 3 years to design and test a engine :like:
 

Odyssey USA

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@Odyssey USA Lower piston ring tension is an attempt at increasing mpg and cafe numbers, sometimes with increased oil consumption (Subaru LOL), and increased blow by from lower ring tension can dirty oil quicker.
Possibly. Surely they tested and got good results between the rings and piston ring grooves. We did it for lower friction and powa!
 

GW’s JL

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Jason from Engineering Explained.

ā€œFenske further explains why GM is making the switch from 0W-20 to 0W-40. Generally speaking, it’s inadvisable to increase the first number or decrease the second number in an engine oil’s viscosity, because it introduces the engine to a viscosity it isn’t designed for. However, increasing the second number isn’t as risky since the whole operating range of 0W-40 oil is within the operating range of 0W-20 oil.ā€
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