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So I just did my first oil change on my 17 Rubi JKU and I decided to use 5W30 (Pennzoil Platinum ultra). The oil change went without a hitch and I really appreciate the Jeep design as far as placing the oil filter up top in the engine bay, unlike the twist off nonsense that I had to spend almost 30 minutes on each time with my Ram 2500 Cummins.

Anyways just a heads up to anyone debating use of the 5W30, I noticed that my oil pressure is not running at 99 psi when merging onto the freeway at a 6% grade like it used to before, and I noticed that it runs much quieter as well. The other thing that I noticed is that the temperature doesn't seem to sky rocket while idling like it used.

Just my experience in case anyone is debating between the 2. Anyone here have similar input?
 

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So I just did my first oil change on my 17 Rubi JKU and I decided to use 5W30 (Pennzoil Platinum ultra). The oil change went without a hitch and I really appreciate the Jeep design as far as placing the oil filter up top in the engine bay, unlike the twist off nonsense that I had to spend almost 30 minutes on each time with my Ram 2500 Cummins.



Anyways just a heads up to anyone debating use of the 5W30, I noticed that my oil pressure is not running at 99 psi when merging onto the freeway at a 6% grade like it used to before, and I noticed that it runs much quieter as well. The other thing that I noticed is that the temperature doesn't seem to sky rocket while idling like it used.



Just my experience in case anyone is debating between the 2. Anyone here have similar input?


Wouldn't 30 weight be thicker in viscosity and therefore increase pressure but also only in cold Temps?


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I made the switch to Pennnzoil Ultra 5W30 at 1,000 miles and I'm not looking back. The engine runs quiet, there is no ticking or tapping even on a cold start. I discussed this at length with people a lot more knowledgeable than me, including some well respected industry experts, and the consensus was it was a smart move. Opinions vary and oil is always a hot topic, but I won't be using a 20 grade oil in my 2016 Rubicon.

There is also verbiage in the owners manual that states 5W30 oil is OK in my engine.
 

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Wouldn't 30 weight be thicker in viscosity and therefore increase pressure but also only in cold Temps?


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The "30" in "5w30" is the hot viscosity. In cold temps 5w20 and 5w30 should have the same viscosity. The difference would be as the oil is warmed up, like in a running engine. The 5w30 should be a little thicker, so it should (as you mentioned) have a slightly higher oil pressure at operating temp.
The only thing I can think of to explain what the OP is saying would be the fact that the Pentastar 3.6 is supposed to have a two stage oil pump set up, where it brings on the second stage when it wants more oil pressure. So the oil pressure can go from around 45 psi to around 90 psi depending on whether or not it is running the second stage oil pump.
 

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There's two schools of thought when it comes to 5W30 vs 5W20

One is that the automakers specify the 20 weight because there's less internal drag and it increases gas mileage by a hair, which ends up being a big number over the whole fleet of cars that they sell

The other is that newer engines have much tighter tolerances than the engines in the old days, so the thicker oils won't protect them as well.
 

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5W30 is fine to use.. It says so in the manual. (At least in my 2016 manual).

Note: MOPAR SAE 5W-30 engine oil approved to FCA Material Standard MS-6395
such as Pennzoil, Shell Helix or equvilant may be used when SAE 5W-20 engine
oil meeting MS-6395 is not available
.

As blkyukon points out, the thinner oil does provide a slight mileage increase. In my case, my engine has never made any noises, so I don;t need the thicker oil. But, there's nothing wrong with using 5W30.
 

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The other is that newer engines have much tighter tolerances than the engines in the old days, so the thicker oils won't protect them as well.

This is true, however a look at a shop manual and the specs and tolerances/clearances for many engines often don't change, yet the oil spec changed from 5w30 to 5w20. Even bearings, rings, cams, oil pumps, etc. remained the same in many cases. That isn't always the case but it was convincing enough for me to swing my Liberty and Rubicon to 5W30. In many instances 20 grade oils were CAFE driven. Ford recently changed 'some' of their engines from 5W20 to 5W30, rumor has it that it was to reduce warranty claims.
 

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I have had 4 3.6L wranglers and have used both 5w20 and 5w30 (always pennzoil platinum) and never noticed one iota of difference. My last 3 have had EVIC so I can monitor oil psi and temps etc. drive the same sound the same get the same mpg.
 

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Same 3.6 in my 2016 Grand Cherokee and 2017 Wrangler. GC calls for 0w-20 (FCA MS-6366, no 5w-30), Wrangler 5w-20 (FCA MS-6395, 5w-30 allowed). Not sure what the dozen and a half other vehicles with the same engine, but I would suspect there are a few more differences between different applications (and need for gas mileage "tuning"). It's a pretty flexible engine. As long as the manual allows for it they shouldn't (not to say they wont try) bust your warranty because of it if you have a powertrain issue...

As far as that ticking and other operating noise, I've heard a few people switching off the pennzoil to mobil 1 (or other synth), same viscosity fixed those issues as well. Unfortunately it's not MS-6395 (but the mobil 1 super is, not sure if it works the same tho) so its a gamble with warranty if something arises in the future.
 

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Hey all you mechanics....the "W" in 5W-20 or in any multi viscosity oil stands for "WINTER" ....not weight.
It means that in standardization tests (SAE) that on an inclined plane, the oil in winter (at a certain cold temperature) flows like a "5" oil, and in warm temps it flows like a SAE 20 oil.
It's kind of like calling a pistol magazine a "clip". It's incorrect, but most people know what is being said.
 

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I think the "w" stands for "wrinkled" down your way :)


(I couldn't resist. Winter jealousy is all as I sit here freezing my ass off in a foot of snow)
 

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I just don't care about this oil stuff, I take it to the dealer and he dumps in what Jeep recommends and I'm out of there. So far I'm batting 100 percent on no engine failures, that's good enough for me. So far my new JK is 6 months old and 2100 miles on it, I'm wondering if I will change my oil this year or next.

trainman
 

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There's two schools of thought when it comes to 5W30 vs 5W20

One is that the automakers specify the 20 weight because there's less internal drag and it increases gas mileage by a hair, which ends up being a big number over the whole fleet of cars that they sell

The other is that newer engines have much tighter tolerances than the engines in the old days, so the thicker oils won't protect them as well.
Both are true.
 

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Apparently these are the "Best".... I dunno

Oils With Benefits...

- Olive oil.
- Canola oil.
- Flaxseed oil.
- Avocado oil.
- Walnut oil.
- Sesame oil.
- Grapeseed oil.

Plan accordingly. I'm mixing a batch up for later .... it's enema Friday!
 
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