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0w 20 or 5w 30

Gwolf

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Hello
Has any one out there running 5w 30 had a check engine light come on?
I was told by my dealer that could happen if I started running 5w30 oil.
I have never heard any one saying this has or would happen.
I thought 5w 30 would be better for towing.
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4-Low

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Are you somebody who is terrified that they’ll void your warranty if 0W20, which is only *recommended* in the manual, is not used? Then use 0W20.

Are you somebody who wants your engine to last longer, have less chance of valvetrain failure, and produce less wear in hot weather? Do you want to use the spec that this engine got for YEARS here in America? The same spec that it currently gets everywhere in the world that doesn’t have the U.S. EPA to contend with? Do you want an engine that doesn’t have dry starts? Oil that doesn’t shear out of grade as quickly? Then use 5W30.

A CEL has nothing to do with oil. It could have something to do with not installing the filter correctly.
 

DiehardTory

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OH My. Get on youtube, look up The Oil Geek .. Watch and Learn... BTW.. Been on 5w-30 since 2013 in our 1st Gen 3.6L JKU.. 5 yrs in '21 JT and now in "23 JT. NO PROBLEMS NO "TICK" & Dlr has no Idea either -- remember the "don't ask - don't Tell".
 

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Gwolf

Gwolf

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Are you somebody who is terrified that they’ll void your warranty if 0W20, which is only *recommended* in the manual, is not used? Then use 0W20.

Are you somebody who wants your engine to last longer, have less chance of valvetrain failure, and produce less wear in hot weather? Do you want to use the spec that this engine got for YEARS here in America? The same spec that it currently gets everywhere in the world that doesn’t have the U.S. EPA to contend with? Do you want an engine that doesn’t have dry starts? Oil that doesn’t shear out of grade as quickly? Then use 5W30.

A CEL has nothing to do with oil. It could have something to do with not installing the filter correctly.
Yes I am look for less wear when towing and in hot weather so I am not terrified, I have 43000 on it already.
 

bmpcamry09

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I was flat out told by the dealer the engine sensors know the oil viscosity which I still say is Bovine Scat
Dealers have become the worst place to get credible information on the very vehicles they sell. You’ll learn way more on an enthusiast forum than anyone at a dealer will tell you. Just gotta wade through the useless posts some times
 

g2020

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The following post is a fact-based introduction to motor oil viscosity grades, for the gasoline engine, listed in 1) the online version of the Jeep Gladiator owner's manual (revised), and 2) the "Mobil 1 Engine Oils Product Guide Sheet".

Motor Oil Compliance Funnel

The pages on motor oil guidance, from the both versions of the owner's manual, are shown in Motor Oil & Oil Filter Service Intervals. See p. 232 from the original owner's manual, and p. 251 from the online version.

Also, Lake Speed Jr has a lot to say about 0W-20 vs. 5W-30 (posted by @Splenda). His findings are supported by data.
 
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Bandit’s Lair

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5w30 should only be used if your running an aftermarket cold air intake. The extra horsepowers need the added protection.
Does this include stickers too? I have a couple so figure an extra 15-20HP. :like:
 

AmosMoses

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Does this include stickers too? I have a couple so figure an extra 15-20HP. :like:
Don't be ridiculous. Stickers are cheap but super classy mods for jeeps but not in the same category as a serious engine mod like a cold air intake.
 

Dilly’S Willy

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The ONLY 3 reasons 5w-30 isn't recommended in these engine are:

- Dealer CAN claim wrong oil used and void warranty (not WILL, CAN).
- The phasers/etc may not have the oil clearances designed for thicker oil and could cause it to shear must faster causing faster breakdown of the oil. (If you can't understand this, don't talk to me...joking but also dead serious).
- It causes SLIGHTLY more friction on the crank/etc increasing emissions output more than designed by manufacturer when they submitted the engine for emissions testing.
 

Guns_N_Rosaries

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I took my truck in yesterday for an oil change. I've always run 0W-20, but my warranty just finished up, so I decided to switch to 5W-30, and the oil change place actually refused to use it. I was already there so I had them just do the normal 0W-20, but I'll probably just switch to doing it myself (also because it was $117 for 5 qts of Mobil One, a filter, and labor).
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