The factory recommended; MS #.. Penzoil Platinum Synthetic but I go 5w30 .

 

What oil do you all use

In 50+ years of vehicle ownership I have always used the recommended OEM type.
No regrets.

 

SuperTech from Wallyworld.

 

Full synthetic, 10W-30

 

Uh ... I thought we were supposed to use 0W-20 in the 3.6l ?

 

Yes, that is what the owners manual says. So why deviate from it…. Forums love to have engine oil wars..lol

 

What's the main bearing clearance? .0025? 10W-30

Bearing Clearance And Oil Viscosity Explained | K1 Technologies

The relationship between bearing clearance and oil viscosity is a delicate balance. Read on for more information on how to get it right!There are some fairly

www.k1technologies.com

Bearing in mind that "W" does not indicate weight. Synthetic 10W-x flows on start-up (unless you're in one of the colder parts of Canada).

 

Some people are of the opinion that 0W-20 is unacceptable for warm weather

 

I can't do temperature math.
I tried to convert UTC time in Excel yesterday and failed at that too.
I'm trying but i keep thinking about Excel column formulas that dont work.

 

Ummm, I get 50 degrees F for top of 0W20 on that chart. I think that might be the low (SOMETIMES) here in the WINTER!!

Based on that chart, I need 10W40...?

0W20 is recommended in BOTH my wife's Tahoe (5.3L V8) and my JLU (3.6)...

 

Since ambient rarely exceeds 40C I'd go with a full synthetic 10W-30

 

Not true here in S. TX. This last summer we had 74 days where temps exceeded 100. For you math folks out there, that's 20% of the year. And there are SEVERAL more days that bump the century mark each year. That's my biggest concern with oil, it's not the lower temp that bothers me so much; most reasonable oil that I would use will still flow WELL below even my worst lows here. But my part of TX is famous for cooking EVERYTHING. Second only to some places in Arizona, or Death Valley...

I am and always have been the type to use whatever is recommended in the manual, and yesterday when I looked again, the manual is a little weird in this regard. In one section it talks about what type of oil to use in each different available engine, but the 3.6L (and only the 3.6L) does not list specific weight in that section. You have to go find the actual fluids chart to see that it recommends 0W20. And it reads like an apology there.

I've read that thinner oil is spec'd not for longevity of the engine or performance, but for fuel economy. That tracks with A LOT of what is "recommended", or OEM equipped in/on our vehicles here in the US. And it's frustrating. My goals have always been durability and performance, in that order. Fuel economy is REALLY far down on the decision matrix.

 

10 C is 50 F .. so is that chart saying that in New England I have to use 0W-20 in the winter and change to 0W-30 in the summer? (Based on 30 C ='s 86 F) Does that even warrant the change, that little of a difference in oils? Actually... shouldn't I just use SW30 year-around? It seems to cover a large spectrum...

 

That chart means nothing for this application, especially with no source cited.
0W20 being recommended below 50*F could be for a Briggs & Stratton mower for all we know, with the chart also including monogrades.

 

There's a difference of opinion about that chart. I was only posting it for those who want to consider the variety of ideas that are out there.


A few years ago, Nissan did a serious study recommending 10W-30, linked below. The following is worth a read. I understand that most of the people who are on phones do not like to go to linked threads :

Do you think that's "thick" oil? Think again!

Recently there has been concerns regarding premature timing-chair wear, which resulted in people using thicker oils. Many people think that when they use a 0W-40, they are putting in a thick oil because it's "40-grade" when it's at normal operating temperature. It turns out that it's not that...

bobistheoilguy.com

 

A few years ago, Nissan did a serious study recommending 10W-30, linked below. The following is worth a read. I understand that most of the people who are on phones do not like to go to linked threads :

It's an interesting read and discussion for sure, but obsolete as it's two API ratings old. I also didn't see any recommendation by Nissan, specifically. Nissan's current lineup recommends 0W20, including their flagship Maxima sedan. The GT-R still recommends M1 0W40. Some of the best UOA's of my well-beaten trail Jeep have been with 0W40 lubricants.

For those seeking additional interesting studies, I recommend searching for Gary Allan on BITOG, regarding using 0W10 in his 2.5L TJ Wrangler. Gary was a great guy (passed in 2011), and experimented with a custom formulation made for him by a tribologist on Bob. Very interesting results. @demarpaint is familiar with his postings.

In the end guys, running a higher viscosity lubricant in your 3.6L is not going to hurt a thing as long as it's pumpable in the cold. I would recommend a 5W30 over a 10W30 if you're in my neck of the woods, but either way, deviating from the recommended 0W20 would be fine. The question is, does it help with longevity over the recommended lubricant? Just about every manufacturer recommends 0W20 now.

 

I wouldn't run an API SM rated motorcycle oil in modern Jeep engine. For roughly the same price as one quart, he could buy a jug of API SP 5W30 and get the benefits of the latest rating.

 

So if I'm reading all these posts correctly, maybe on my next oil change I should drain the 0W-20 and put some 05W-30 in there? I drive: 25% suburbs, 25% highway and 50% city (Boston, MA area). That sound like a plan?

 

I'm in Boston too, and see no reason to deviate from the recommended viscosity. Perhaps in July, if it makes you feel better. Right now, we're already driving around with likely a 30 grade anyway, due to it being winter.
There are a myriad of other things I would be concerned with in a late model Jeep besides the recommend engine lubricant. My wife has been researching a new vehicle and is not fond of the eTorque system and some of the gremlins people are dealing with. Of course, that goes for all brands. My best friend's wife just a bought a new Bronco as their son has a JK and has had a lot of issues when it reached 90-100K miles.

 

Yes, if I lived in Boston then I'd use 5W-30.


Most parts of the country are warm enough for 10W-30, so that's why I'm always running that up the flagpole.

 

Yes, if I lived in Boston then I'd use 5W-30.

Most parts of the country are warm enough for 10W-30, so that's why I'm always running that up the flagpole.

Define "most", MuffinTop.

I ask that because I've read the arguments for and against using the recommended oil (0W-20) in a JL, but being in Alaska, with our cooler climate (it was -26 F for three consecutive mornings two weeks ago), I am inclined to stick with the 0W-20. Unless somebody can give me a strong argument to the contrary.

 

If your Jeep is out of the factory warranty period you can use whatever oil you choose. However, if it is still under warranty be careful. Stellantis looks for anything they can to deny an expensive warranty claim.

3.3.Maintenance Costs Not Covered
Your warranties do not cover the costs of repairing damage caused by poor or improper maintenance. Nor do they cover damage caused by the use of contaminated fuels, or by the use of fuels, oils, lubricants, cleaners or fluids other than those recommended in your Owner’s Manual.

 

If your Jeep is out of the factory warranty period you can use whatever oil you choose. However, if it is still under warranty be careful. Stellantis looks for anything they can to deny an expensive warranty claim.

3.3.Maintenance Costs Not Covered
Your warranties do not cover the costs of repairing damage caused by poor or improper maintenance. Nor do they cover damage caused by the use of contaminated fuels, or by the use of fuels, oils, lubricants, cleaners or fluids other than those recommended in your Owner’s Manual.

My wife and I sued and won against GM twenty years ago. They will certainly try to use all means to deny the claim, but they have to prove that using a non-recommended viscosity caused the damage.

 

most of my fluids are Amsoil since it’s 2nd oil change.

 

I think the insight here is that "W" does not stand for weight, so a 10W-30 will flow just as fast on start-up as a 5W-30. The only difference between the two would be at temps below zero F.


Since I've moved to Dallas, I've been wishing AMSOil would offer their Signature product in 15W-30. I'm not holding my breath because they're not going to see the need for it, being in the upper midwest.


For my gulf coast vehicles, I'm thinking about using 20W-40 at the next oil change. Except I've still got a box of their 10W-30 that I moved here from south NJ to use up.

 

"W does not stand for weight, so a a 10W-30 will flow just as fast on start-up as a 5W-30. The only difference between the two would be at temps below zero F."

I hope that we can respectfully disagree, particularly regarding your point, "The only difference [is] at temps below zero".

I will argue that temperatures "below zero" aren't a special condition for oil which abruptly no longer applies as we consider a temperature above zero; that is, oil that is 0W-, 5W- or 10W- do not suddenly transition into the same viscosity as soon as they are at a temperature above zero, which is, I believe, what you are implying when you write that they "will all flow just as fast."
What I believe is that, for example, a 0W- is a starting weight (a viscosity) that is thinner and will flow faster at a certain below zero temperature than a 10W- oil at that same certain below zero temperature, e.g., 0° F. At this you may agree....

However, you probably disagree with my belief that, for example, as a 0W-30 oil gradually warms up it will remain thinner and flow faster than a 10W-30 oil; and that this difference between the oils' viscosities will only diminish gradually (proportional to the temperature) as their temperature rises until they both reach, let's say 100° (which is the standard temperature for the second number), at which point their viscosity and flow rate will finally be about the same (because they both share the second number, 30). The key part here is that their difference will diminish gradually -- meaning that there will still be some difference in viscosity at some intermediate temperature such as, for example, 50°.
It is this difference in viscosity at 50° or thereabouts that is my concern for oil flow at an early morning start-up.

 

I recommend reviewing SAE J300 to see the Winter grade assignments. It will explain the testing procedure.

 

So lots of discussion on oil grades. I am curious if more important aspect is distance between change intervals. Especially with the big temp differences North/South. We have seen "normal" oil change intervals of 3k, then 4,5 and now 10k. Yes full synthetic oil is better. But. Who out here has not seen difference in the color/ texture as it degrades from original honey color to jet black at 10k. Maybe 7 or 8 k needs to be the target. Any thoughts.

 

That is why the OEM's have spent millions developing oil change interval algorithms. In my experience, most are very good. Back when they were first being implemented, I confirmed their accuracy in my vehicles via UOA tests. It was fun to have some nice trends, especially comparing winter and summer intervals.

IMO, The 3K oil change was beaten into us by the quick lube industry back when carbureted vehicles were getting sludged on extended drains. As vehicle and motor oil technology evolved, the change interval extended, which is a good thing economically and ecologically. Europeans have been doing 15000K(just under 10Kmiles) and 30000K(just under 20K miles) intervals for a long time now.

 

Does ambient temperature mean anything after the engine warms up? I say NO. Engine temp is regulated by the thermostat. Living in Minnesota in the 1960s, winter temps dropped to -40f. 10-30 non-synthetic worked well.
5-30 synthetic will be my new standard in all of my vehicles.