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Flip

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Walnut blasting the backside of the valves is not needed--the 3.6L is an MPI engine, not DI. Use a good fuel injector cleaner frequently.

Run 5W-30 or 0W-30 oil and change every 5K miles.

Run an oil filter which can filter down to 20 microns @ 99% efficiency. Take EXTREME care not to overtighten the oil filter cap.

Run a top quality air filter--not a K&N type.

If you run a catch can, make sure it's NOT a UPR which has a crappy hose design and will crack and leak on your passenger oxygen sensor and ruin it.

Change your axles and transfer case fluid early and often. Use 75W-140 in the axles despite what FCA says. If a Rubicon, pot the locking sensors with epoxy at 5K miles when you change fluid for the first time.

Change your automatic transmission fluid and filter at 50K miles and perform 3 or 4 dump and fills within the next 10K miles to replace nearly all of the old fluid.

Be prepared to change your auxiliary battery in about 3 years or less. Change both batteries when you do.

Drive your Jeep frequently and enjoy!
If I could just pick your brain for one minute, please? :please:

Which oil would you recommend for added protection/longevity, the 5W-30 or 0W-30?

Change your axles and transfer case fluid early and often; how early and how often, at what mileage would you recommend?

If you run a catch can, make sure it's NOT a UPR: I have no idea how to figure this out, so I won't even ask.
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CarbonSteel

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If I could just pick your brain for one minute, please? :please:

Which oil would you recommend for added protection/longevity, the 5W-30 or 0W-30?

Change your axles and transfer case fluid early and often; how early and how often, at what mileage would you recommend?

If you run a catch can, make sure it's NOT a UPR: I have no idea how to figure this out, so I won't even ask.
Either will provide more protection and reduced wear versus xW-20. It is pretty cold in CO during the winter so I run 0W-30 for about 1/2 the year. With that said, they are both 30 viscosity--the number to the left of the "W" is the winter rating so choose the one that best matches your winter needs.

I changed my factory fill at 5K, 10K, and 20K miles for non re-geaed axles and the transfer case. I have a different change interval for a re-geared axle. I use 75W-140 in both axles despite what FCA recommends. I use ATF+4 in the transfer case.

After the 20K change, I change every 25K after that in these Dana 44 Advantek axles.

The UPR catch can is an add-on so you would know if you had it.
 

Flip

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Either will provide more protection and reduced wear versus xW-20. It is pretty cold in CO during the winter so I run 0W-30 for about 1/2 the year. With that said, they are both 30 viscosity--the number to the left of the "W" is the winter rating so choose the one that best matches your winter needs.

I changed my factory fill at 5K, 10K, and 20K miles for non re-geaed axles and the transfer case. I have a different change interval for a re-geared axle. I use 75W-140 in both axles despite what FCA recommends. I use ATF+4 in the transfer case.

After the 20K change, I change every 25K after that in these Dana 44 Advantek axles.

The UPR catch can is an add-on so you would know if you had it.
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CarbonSteel

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Anyone recommend LiquiMoly to combat the rocker issue?
I have never been a big fan of oil additives (not saying that may not have their place). I would be more inclined to use a high-quality oil, keep the OCI at 5K, and up the viscosity 1 level. There does not seem to be a rhyme or reason for rocker failures in the 3.6L. Some people have them and others do not.

@mwilk012 may have some thoughts...
 

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Soggybottomboy

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Someone earlier mentioned fuel injection cleaner. If you always run top tier gas is injection cleaner necessary?

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Keep up with required maintenance most modern engines will last a long time, if not they are probably defective from the start.
 

mwilk012

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Anyone recommend LiquiMoly to combat the rocker issue?
LiquiMoly is just a brand name. What product are you referring to?

No oil is going to help the build quality of these roller bearings. Good clean oil is always going to be the best thing we can hope for.
 

norbert

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LiquiMoly is just a brand name. What product are you referring to?

No oil is going to help the build quality of these roller bearings. Good clean oil is always going to be the best thing we can hope for.
My bad. I was thinking of the Hydraulic Lifter additive. And maybe ceratec.

The thin oil might be leaving the rocker's dry after a long period? This might give its some protection.
 

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CarbonSteel

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My bad. I was thinking of the Hydraulic Lifter additive. And maybe ceratec.

The thin oil might be leaving the rocker's dry after a long period? This might give its some protection.
Upping the viscosity of the oil would provide more protection, but a bad design or defective part is not going to be resolved by the oil or additives.

I run xW-30 and have 70K miles on mine. I have a friend in Texas who runs xW-40 in his and has over 110K on it now.
 

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The dilemma for those who are still under warranty is that the owners manual calls for 0W20 with the API starburst symbol. If you use some other viscosity like 5w20 or 0w30 or a non-API-certified oil (such as Amsoil) and you end up with an engine problem, the dealer can point to the incorrect oil being used and deny warranty coverage of the failed lubricated part. Using an oil that is arguably more protective and better for engine longevity but does not meet the manufacturer's written specification may lead to warranty denial. The bad part is they hold all the cards and your arguments for why the failure was not caused by your choice of oil will go unheard. It is a dilemma that is playing out in my head as I approach my first oil change.
 
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Cutterone

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2021 Sahara 6sp, I run 5w-20, how does that compare to perhaps switching to 0w-30 or 5w-30...I'm in NH so deal with the frigid winter, however she is garage kept, and garage is part of the house so almost never drops below freezing in the winter, which is nice for morning start-ups...
 

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The dilemma for those who are still under warranty is that the owners manual calls for 0W20 with the API starburst symbol. If you use some other viscosity like 5w20 or 0w30 or a non-API-certified oil (such as Amsoil) and you end up with an engine problem, the dealer can point to the incorrect oil being used and deny warranty coverage of the failed lubricated part. Using an oil that is arguably more protective and better for engine longevity but does not meet the manufacturer's written specification may lead to warranty denial. The bad part is they hold all the cards and your arguments for why the failure was not caused by your choice of oil will go unheard. It is a dilemma that is playing out in my head as I approach my first oil change.
While not a cheap solution, have the dealer do the oil change then when you get home drain and refill to the viscosity of your choosing.
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