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grimmjeeper

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PUP, 0W-20 in winter and 5W-30 in other months 🤩👍 Mopar for other fluids and Mopar filters
Not for a diesel. 15w40 is a far better choice for the 3.0.
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Tr4ckD4ys

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Like I said, I thought this would be a good resource to ask for help from people with similar mods and real-world feedback. Again, people don't fail to disappoint me. Not hard to be helpful. If you don't have something to say to help, don't bother. Not hard to be nice.
I mean if I had your attitude I too would think everybody was disappointing. Also this is the internet. Where were you the last 30 years?
 

grimmjeeper

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@harrish24

Your comment "this forum website would be helpful, but this has proven otherwise, and that people have no incentive to help one another." is absolutely frigging laughable at best.

You started a thread and asked for hand holding because you are too lazy to forum search and read. Suggest you go seek help on FB.
To be fair, there is so much BS flowing through the oil threads that even spending days reading them doesn't get you useful information.

Then again, starting another thread like this will likely get you the same river of BS flowing through it. Expecting a forum to be helpful when it comes to oil is naive at best.
 
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harrish24

harrish24

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I mean if I had your attitude I too would think everybody was disappointing. Also this is the internet. Where were you the last 30 years?
well.... im only 19.... so i havent been on the internet long. helicopter mom didnt help
 
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harrish24

harrish24

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Oh boy… can you be a bit more dramatic?
If your situation is as you say, then I recommend using “ChatGPT 5.1 Thinking” mode and specifically ask it to summarize the threads on jlwranglerforums.com related to fluids. I’ve done it before in it was 95% correct in its distillation of information. For example, you could ask it “According to forum members, what’s the definitive best engine oil for my engine with xxx miles.”

This will save you lots of time and prevent you from just getting opinion without knowing whether that opinion serves your definition of “best”.

Or to give to you more candidly: The best advice you can get is already here. You just don’t have the time to find it. You can’t expect though that anybody here is going to recite the entire wealth of knowledge of this forum regarding each fluid in your thread.
Again, just looking for feedback for my situation and my needs with real world feedback. Not looking to go to an oil thread for someone towing 24/7 or in different climates. whatever it is, just looking out for myself. also, have been using chat gpt but its been no help.
 

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grimmjeeper

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well.... im only 19.... so i havent been on the internet long. helicopter mom didnt help
Here's something you missed out on then. A valuable life lesson.

 

Tr4ckD4ys

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Again, just looking for feedback for my situation and my needs with real world feedback. Not looking to go to an oil thread for someone towing 24/7 or in different climates. whatever it is, just looking out for myself. also, have been using chat gpt but its been no help.
I can help. I’m usually no fan of reposting AI content but if you DM me exactly what fluids you want to know the summary of, I will use my 200$ ChatGPT pro subscription for you.

EDIT: Include you engine, mileage and model year.
 

Tr4ckD4ys

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Ok so here I go breaking my own rules. For your engine, here is what ChatGPT said is the best according to threads on this forum:
- Engine Oil: “Popular enthusiast choices with UOA backing:
  • Amsoil Euro/EFM 5W-40 (MS-12991)
  • Motul 8100 X-cess Gen2 / X-clean 5W-40 (MS-12991, mid-SAPS)
  • From the threads, the real “best” is: Any full-synthetic 5W-40 that clearly says “MS-12991” and API SN/SN+ or SP on the label. Brand is secondary to that stamp.
- Trans Case: OEM: Mopar ATF+4 (e.g., P/N 68218057AC/AB depending on bottle)
- Transmission:
  • Fluid:
    • Primary choice: Mopar 8&9 Speed ATF
    • Equivalent: ZF Lifeguard 8 (or 9)
  • Specs that matter:
    • Designed for ZF 8HP transmissions
    • ~26 cSt @ 40°C, 5.6 cSt @ 100°C (don’t substitute a thicker universal ATF).
  • Service:
  • Drain/fill (no flush), 2–3 cycles, change pan/filter, ~60k mi normal / ~40k mi severe
- Differentials:
If you want a set-and-forget, high-margin setup for a 3.0 EcoDiesel JL that’s tuned, lifted, or sees towing/off-road:
  • Front M210:
    • GL-5 full synthetic 75W-90
  • Rear M220:
    • GL-5 full synthetic 75W-140
  • Additive:
    • Only if you have Trac-Lok LSD. No additive for Rubicon Tru-Lok lockers.
  • Interval:
    • 20–25k miles in real use, sooner after water crossings or gear swaps
- Coolant: MOPAR Standard as specified in manual.
 

grimmjeeper

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Ok so here I go breaking my own rules. For your engine, here is what ChatGPT said is the best according to threads on this forum:
- Engine Oil: “Popular enthusiast choices with UOA backing:
  • Amsoil Euro/EFM 5W-40 (MS-12991)
  • Motul 8100 X-cess Gen2 / X-clean 5W-40 (MS-12991, mid-SAPS)
  • From the threads, the real “best” is: Any full-synthetic 5W-40 that clearly says “MS-12991” and API SN/SN+ or SP on the label. Brand is secondary to that stamp.
- Trans Case: OEM: Mopar ATF+4 (e.g., P/N 68218057AC/AB depending on bottle)
- Transmission:
  • Fluid:
    • Primary choice: Mopar 8&9 Speed ATF
    • Equivalent: ZF Lifeguard 8 (or 9)
  • Specs that matter:
    • Designed for ZF 8HP transmissions
    • ~26 cSt @ 40°C, 5.6 cSt @ 100°C (don’t substitute a thicker universal ATF).
  • Service:
  • Drain/fill (no flush), 2–3 cycles, change pan/filter, ~60k mi normal / ~40k mi severe
- Differentials:
If you want a set-and-forget, high-margin setup for a 3.0 EcoDiesel JL that’s tuned, lifted, or sees towing/off-road:
  • Front M210:
    • GL-5 full synthetic 75W-90
  • Rear M220:
    • GL-5 full synthetic 75W-140
  • Additive:
    • Only if you have Trac-Lok LSD. No additive for Rubicon Tru-Lok lockers.
  • Interval:
    • 20–25k miles in real use, sooner after water crossings or gear swaps
- Coolant: MOPAR Standard as specified in manual.
Amsoi hasn't been certified to MS-12991.

And the results don't get any better from there.
 

Tr4ckD4ys

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Amsoi hasn't been certified to MS-12991.

And the results don't get any better from there.
Hence my rule to not repost AI generated content… though I’m curious - the general gist of the output seems correct, but it did get some details wrong!
 

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SlickRicksWilly

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im only 19
That explains it, my son is your age. I will try to help but have a feeling you will take it as me being a condescending asshole, which is not my intent.

No one can help you for 2 reasons. First, there is not an definitive answer for your question and if there is no one on this forum knows it as fact. Second, there are so many variables that one person's opinion, experience, or real data collection still will not match your situation.

The best advice I have is don't expect other people to do the work for you. If you want you vehicle to last, change you fluids at regular maintenance intervals. Oil between 3-5k miles. As someone who has already had to have 3.6 replaced, I would not follow the maintenance reminder because I THINK the intervals are too long.

Then take samples and send them into Blackstone or whoever else does oil analysis tests. Try different types of oils and compare the results you get. This information will be specific to you and the best knowledge you will gain. It can also be an early warning for issues with the components of which fluid is being tested.

Additionally, every vehicle forum I have ever been on has 100s of these fluids threads and they are all essentially the same. People giving opinions, sharing their own personal experiences, and some will post oil analysis results. At the end there is still not a definitive answer as to what is best.

You are new here and it sounds like new to Internet forums. Almost every post from anyone will be met with sarcasm and jokes. As you read through the forum you will better understand that is just the vibe and are here to help each other out, have fun, occasionally make each laugh, and to discuss vehicles we love. Most of the time we are not meant to be dicks.

Finally, saying no one is helping you, simply isn't true. Several people directly answered your question. As shown below. But with any and all "what is the best" threads you will never get a definitive answer. Take in the info you get, see people's pros and cons and make the best decision you can.

MOPAR, because it's easiest. One stop shop, at the dealer, getting manufacturer recommended fluids. Change them at the recommended intervals and you don't need much more... There are TONS of boutique fluids out there, it's a black hole of research, and in the end you'll be running all over town or ordering from 5 different places... Just a waste of precious time. In the end you won't keep your Jeep forever, and the next guy will take it to Jiffy Lube, so why bother lol...
I have always used Amsoil in all my vehicles including my Harley’s. Best oil in my opinion. They have fluids for engine, diffs, and transmission.
Engine: Pennzoil
Coolant: Mopar
Transmission and transfer case: Mopar
Differential: Royal Purple
Cooking: Olive

Best deal: typically Amazon

Disclaimer: I'm not saying these are the best, but just answering the question. My opinion is that it isn't as much as what brand you use vs how often you change it.
PUP, 0W-20 in winter and 5W-30 in other months 🤩👍 Mopar for other fluids and Mopar filters
You probably assumed this was a dick move, but I called in @Jeep Junkie because he changes his oil more than anyone I met and I believe sends all the samples in for analysis.

@Jeep Junkie , Are you gonna let this guy move in on your territory like this?
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Im sure there's 100 threads here about all sorts of fluids, but rather than scavenging for information that leaves me questioning, I'd like to address them all here.

What is everyone using for Engine Oil, Coolant, Transmission Fluid, Differential Oil, Fuel Additives, and anything else? And why? Who gets the best deals from where? What makes one fluid/brand better than another? If Im missing any other obvious questions, please tell me!
What a stupid question! What kind of zealot are you?


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Pain Killer

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The problem is I work full-time and go to night school full-time. I have enough time to post to ask a question, and try to receive feedback. I don't have 15 or 20 minutes to sit here and try to find 1 good post about fluids. I thought this forum website would be helpful, but this has proven otherwise, and that people have no incentive to help one another.
Just use what the manufacturer recommends. Who Knows better?
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