List of Chrysler MS-12991 Engine Oil for the 3.0 EcoDiesel Jeep Wrangler

[Wrangler man]

Figured I would give some insight from my personal experience thus far on the whole "What oil to run?" debate.

To start, I have zero clue what oil was in this beast when I bought it. I can only assume it was mopar packaged Pennzoil 5w40. Didn't run it long enough to care though since I changed it pretty quickly after doing a deep dive on what the community here said to go for.

So, first oil change was an ecoguard filter with Castrol Euro 5w40. This stuff meets MS-12991 and can be had for fairly cheap locally. Great. Box ticked, we should be golden right?
Yeah...right. Some of you probably already know this or at least are maybe in the loop but I've been having a devil of a time trying to pin point what the hell was causing me to go into Regen so frequently. I tried running a fuel catalyst to try and ignite the soot faster in the DPF, I ran a tank of Hot Shots Extreme to see if my injectors were gummed up, I did a forced regen to see if there was an issue with the sensors. This was driving me bonkers. I basically had narrowed it down to 2 culprits after exhausting everything else (literally). 1) the DPF was trashed and needed to either be pulled and cleaned the old fashioned way or replaced. 2) the oil was causing excess soot formation.

Seeing as Oil was the cheapest fix, I figured it was worth at least eliminating it as a cause before jumping down a more expensive rabbit hole. I ended up jumping down a much more murky rabbit hole instead when I started digging up info from the Ram side of the house and looking at their oil analysis threads. Turns out the Castrol is great for keeping wear down and the metal counts in check...what does become an issue though is when you realize its a full saps oil....like ALOT of MS-12991 and ACEA A3/B4 oils.

Full Saps is the last damn thing anyone should be running on a motor equipped with a particulate filter unless they want to burn out their emissions system components early or straight pipe the nasties care free (I'd rather not feel the wrath of my CARB state emissions legally so option 2 is a no go). I've read a couple mixed reports saying the MS-12991 is supposed to be a "mid/low saps oil" but that's bull$hit if it's also meeting ACEA A3/B4 so I don't buy that argument at all.

What to do then? The Ram ecodiesel guys seem to be on to something with certain mid saps oils, particularly ones that meet BMW's Long Life 04 spec. The TL;DR version is the while BMW LL01 is meant for cars without particulate filters, BMW LL04 is. I've owned countless BMW's in my life so when it comes to an oil that meets their requirements, it's gotta be good stuff. The flavor the ram dudes are all bananas over is Amsoil MS 5W40 Euro spec (red label).

Yes, yes, I know, it's Amsoil. It's the nectar of the dorks that think Amsoil is the god of oils. I was skeptical as hell too, especially given that it doesn't meet ANY of the recommendations in the owners manual (there's plenty of Rotela T6 guys here that will tell you those recommendations are about as useful as the paper they're printed on). But given the data I was seeing in the oil analysis charts being posted, I couldn't find a reason to not give it a shot (other than the obvious "You'll void your warranty!" cricket on my shoulder). With less than 3000 miles on the Castrol, I said screw it, ordered it, and swapped it in with a fresh ecoguard filter.

First 20 or so miles seemed like nothing changed. No new noises (if anything it sounds a little quieter), no weird vibrations. Soot accumulation was still sky rocketing like crazy. I figured it might take a bit to show any signs of improvement so I ignored it. Sure enough, within 50 miles passive regen was actually making a noticeable difference for a change. Before this I could run for 100's of miles and barely burn off 30%. Now I was burning 10% every 15-20 miles like it was effortless. The soot accumulation is now WAY more in line with what I would expect for normal operation, even with mostly city driving. It's literally a night and day difference. How much of this is down to Amsoil's blend or just changing to an ACEA C3 oil with LL04 specs is up in the air for me. One thing is for damn certain though, I'm staying the hell away from MS-12991 from now on.

I'll run this oil for 5000 miles and report back with a no BS sample report to show whether or not I'm killing my internals by intentionally ignoring the owners manual. The initial results though are down right amazing to see with my Scangauge. Oil temps are still right on the money like they were before and pressure (as accurate as the dash is anyway) hasn't changed a bit. So far so good.

In your research did you call Amsoil asking what their recommendation would be for the EcoDiesel? Or did you just go based off of what the Ram guys said. Either way I'm very interested to hear your 5,000 Mi review and so far based on your early experiences it sounds promising. The FCA recommended oil may be quite suitable for the 3.0 EcoDiesel but not piggybacked with the mandatory highly complicated DEF system on top of it. Your search for the facts and the reality of what is best is quite appreciated. Please keep us informed.

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[DewHawk]

In your research did you call Amsoil asking what their recommendation would be for the EcoDiesel? Or did you just go based off of what the Ram guys said. Either way I'm very interested to hear your 5,000 Mi review and so far based on your early experiences it sounds promising. The FCA recommended oil may be quite suitable for the 3.0 EcoDiesel but not piggybacked with the mandatory highly complicated DEF system on top of it. Your search for the facts and the reality of what is best is quite appreciated. Please keep us informed.

I haven't personally talked to a rep from Amsoil but there's been plenty of others in the past that have. While they don't have anything currently that meets our exact specs, the closest oil they have is 5w40 FS European synthetic (silver label). The big difference here is that FS is a full saps oil like most of the recommended 5W40's that meet MS-12991 vs what I'm running which is a mid saps. The difference in manufacturer approvals is a big giveaway too. FS meets BMW LL01 spec whereas MS meets LL04. Pretty obvious reason why if you think about it. Reference here: amsoil chart (you're looking for AFL and EFM on this list.)
What's more curious here is the fact the red label MS has routinely shown to be better at reducing wear metals and particulates in UOA reports from the ram owners than silver label FS from the same brand. Not sure why that is because based on MS-12991's logic, the FS should be protecting the internals better, not worse than an equivalent oil that doesn't meet the recommended specs.