2025 Ram Rebel I6 SO Issues

[BelligerentRhino]

I know this is starting to become a trend in the forums, but I started getting my Cylinder miss fire codes before the wear in period of the engine(under 500 Miles). Its back at the dealership for the second time so far. I really like Inline engines, but this one is putting me through some grief. First misfire codes at 390 miles cylinders 3,4,5 all stored. Second round of codes cylinders 5,3 stored and cylinder 2 pending. I also received BCM U0155-00, ESM U0402-00, U145D-00 Stored. It seems to be miss firing on start and the dealership cant figure it out it seems. Anyone else running into problems? For the first week with the truck this is far too many check engine codes!

 

[Six Turboed]

One week in and not a problem. Will keep and eye open though. These are not new motors, they have been in vehicles now for a couple years. Just the first year for the truck application. One thing I did notice is that it takes longer than any motor I have had to come down to idle after start up. I suppose it is because it is coming up to temperature????? Hope they get it fixed for you. Let us know how it goes.

 

[JimfromAZ]

I got a 2025 Rebel 1500 with the Hurricane and so far so good. 650ish miles and I don't think about the 5.7 hemi at all. What I can say for certain is the truck shifts fast and the shifts are very pronounced so they feel rushed in a sense. I can say that, since reading the forums, I am nervous now that I will get some issue or CEL. I shouldn't be but now I think about it.

 

[DanAR]

I got a 2025 Rebel 1500 with the Hurricane and so far so good. 650ish miles and I don't think about the 5.7 hemi at all. What I can say for certain is the truck shifts fast and the shifts are very pronounced so they feel rushed in a sense. I can say that, since reading the forums, I am nervous now that I will get some issue or CEL. I shouldn't be but now I think about it.

That’s what these forums will do with you - mess with your mind. After I bought my 23 and reading these forums all I could think about was the Hemi tick, warped exhaust manifolds and rear window leaks. It will start to pass after awhile.

 

[bgenlvtex]

I don't have one in a truck, but I do have a 2023 Wagoneer S2 with the SO Hurricane .

Like all FCA/Stellantis products before I ever left the dealership I seated all the fuses/relays/breakers in the TIPM and have had zero problems in 16k miles.

*I bought a 2024 2500 about 3 weeks ago, same/same, not a single fuse was seated fully in the TIPM.

 

[jlgomez10]

Similar. My 2025 SST Hurricane less than 1-kmiles has stored misfire codes. I just started another thread on this. We spotted the CEL on 8/17 on startup (it had refused the remote start). I read the codes (P0300/P0304), left it parked, and took it to the dealer on first available appointment (8/20).

My SA is speculating that 87octane in the Phoenix heat = not good and I've read other threads blaming contaminated fuel. The SA was doing research into any service bulletins, he seemed to think the octane correlation was mentioned in one, but it could just be a red herring.

 

[turkeybird56]

Similar. My 2025 SST Hurricane less than 1-kmiles has stored misfire codes. I just started another thread on this. We spotted the CEL on 8/17 on startup (it had refused the remote start). I read the codes (P0300/P0304), left it parked, and took it to the dealer on first available appointment (8/20).

My SA is speculating that 87octane in the Phoenix heat = not good and I've read other threads blaming contaminated fuel. The SA was doing research into any service bulletins, he seemed to think the octane correlation was mentioned in one, but it could just be a red herring.

SAYS in the SST manual for the SO Motors to Run Higher Octane fuel when towing, see below ref hot temps.

 

[jlgomez10]

I get that it performs better on 91 for towing and high temps, but that screen capture doesn't indicate it is required. Even so, I certainly would not expect it to cause misfires.

Also, I haven't towed anything yet.

 

[turkeybird56]

I get that it performs better on 91 for towing and high temps, but that screen capture doesn't indicate it is required. Even so, I certainly would not expect it to cause misfires.

Also, I haven't towed anything yet.

Sorry, can only send U what I got. My older son, is on a trip from NJ to FL and soon back to NJ and hoping he report back on the truck. It is a 2025 Lonestar with SO Motor. I also suggested to him to run higher Octane fuel, unknown if he did/is lol.

ADDED: As far as misfires, unknown if the engine is set up to adjust spark advancement etc ref fuel like the Hemi's were. Just not enough info out there and almost, NO reported longevity except for a new owners in here reporting codes and mis-fires. Somebody a lot better mechanically inclined/educated would have to chime in. All of this is why I am holding out on upgrading from my early build 5th Gen Hemi to a 2025, just not enough info or facts.

OP, I wish U well with the issues and a quick resolve.

ADDED: The info to check the TIPM's and seating of fuses may be valid as there were a lot of issues just on this when the 5th Gens came out, IIRC, back to late 2018/early 2019. I checked my fuse box and there were a couple not seated properly, but may be conjecture on some people's point of view.

 

[rule18]

I get that it performs better on 91 for towing and high temps, but that screen capture doesn't indicate it is required. Even so, I certainly would not expect it to cause misfires.

Also, I haven't towed anything yet.

No, but it does say that it will run better, and they seem to split out high temps from towing:

 

[jlgomez10]

Sorry, can only send U what I got. My older son, is on a trip from NJ to FL and soon back to NJ and hoping he report back on the truck. It is a 2025 Lonestar with SO Motor. I also suggested to him to run higher Octane fuel, unknown if he did/is lol.

No, that's fair and thank you for responding. You're spot on that all this is conjecture - and super frustrating. Someone mentioned spark timing and that is a thought I had, too. It's just that a modern ECU should be able to adjust to those conditions and advance or retard timing based existing conditions and fuels.

I'll post with dealer results when I get them...

Thanks, again.

 

[jlgomez10]

Just a follow-up (that I also posted to my thread in the Engine sub-forum), my service advisor appended this case to the work order printout.

From Case Number S23018000005 Rev B; Release Date October 2023:
"Fuel usage in S.O. engine applications should be 87+ octane fuel only, however premium fuel (91+) may be required while driving in heavily loaded or hot conditions until an engineering update becomes available" [Emphasis mine] So they've known about it for a while... here's hoping someone is making progress on a permanent fix.

 

[turkeybird56]

Just a follow-up (that I also posted to my thread in the Engine sub-forum), my service advisor appended this case to the work order printout.

From Case Number S23018000005 Rev B; Release Date October 2023:
"Fuel usage in S.O. engine applications should be 87+ octane fuel only, however premium fuel (91+) may be required while driving in heavily loaded or hot conditions until an engineering update becomes available" [Emphasis mine] So they've known about it for a while... here's hoping someone is making progress on a permanent fix.

I sure hope it is soon, and not like the fix for the U Connect 5 systems with the ole: Hey it's coming, lol.

 

[turkeybird56]

OK, just got a post from my son. He is on a trip from NJ, to FL, to NJ. He is on way back with a stop I think in Atlanta. He reports:


New ride ran flawlessly...been running Plus...
Highway average 21 mpg
550 miles to the tank per dashboard

 

[turkeybird56]

Just a follow-up (that I also posted to my thread in the Engine sub-forum), my service advisor appended this case to the work order printout.

From Case Number S23018000005 Rev B; Release Date October 2023:
"Fuel usage in S.O. engine applications should be 87+ octane fuel only, however premium fuel (91+) may be required while driving in heavily loaded or hot conditions until an engineering update becomes available" [Emphasis mine] So they've known about it for a while... here's hoping someone is making progress on a permanent fix.

NOT SURPRISED they came out with USE betta fuel (Octane). They trying to force so much more outta a smaller displacement engine. They just gotta be running harder with the Turbos to push out the hp, etc, IMHO.

The ole Displacement vs Replacement analogy.

 

[carlylelocke]

OK, just got a post from my son. He is on a trip from NJ, to FL, to NJ. He is on way back with a stop I think in Atlanta. He reports:


New ride ran flawlessly...been running Plus...
Highway average 21 mpg
550 miles to the tank per dashboard

Hand calculated MPG or from the computer?

 

[DanAR]

Good question. The computer on my 23 Limited is way off. Never once has it been within 1 mpg of my calculated mileage, more typically 1.4-1.6 mpg too high. It’s the least accurate one I’ve experienced in one of our cars.

 

[turkeybird56]

Hand calculated MPG or from the computer?

Dunno, but knowing my kid, Computer. I'll see when he gets back to his home if he kept all the receipts and did a trip calculation by hand? TBH, doubt he would do that, that is something I would do. I ran a 4050 mile trip in 2018 with my then brand new 5th Gen Hemi and got 21.8 mpg average for entire trip. But that is apples to oranges.