2025 1500 Laramie SST (SO) throwing P0304 code

[jlgomez10]

My 2025 is in the shop for a P0300/0304 codes (misfire) with a steady CEL on the dash (960 miles on the odometer).


So far, the service advisor has said they're looking at it as a fueling issue related to octane and excessive heat. That is, 87octane from Costco and typical Phoenix weather do not play nice in the standard output Hurricane. They haven't called me back to pick it up, so the diagnosis may change, but I would appreciate some insight from the forum on what to expect.
Honestly, we would not have bought it had we known it would require premium fuel (the manual states 87 is fine) and this is the second visit to the shop in less than 1000miles (other issues were not related to the P030x codes); so I'm not looking to accept the "use premium gas during the summer" as a solution.

I'll keep the forum posted, if there is interest.

Any thoughts or advice?

 

[2012RAM1500RT]

I'm not sure there will be a whole lot of help from here or not, I think there is only a very few people on here that has bought one of these so far so seeing what you go through may show others what to expect. I know that didn't help you at all but I'm interested in seeing what happens. Sorry for your situation and hope everything works out for you.

 

[jlgomez10]

Just got my SST back and the service comments basically state to use 91 octane under heavy loads and/or when driving in a typical Phoenix summer (/sarcasm) "until an engineering update becomes available".

The service advisor acknowledges this should be an ECU programming fix, but has no timeframe. The work order referenced and attached a Case S2318000005 Rev B from October 2023 suggesting to me that RAM has known about this for some time.

From the noted case:
"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"

 

[Wild one]

Just got my SST back and the service comments basically state to use 91 octane under heavy loads and/or when driving in a typical Phoenix summer (/sarcasm) "until an engineering update becomes available".

The service advisor acknowledges this should be an ECU programming fix, but has no timeframe. The work order referenced and attached a Case S2318000005 Rev B from October 2023 suggesting to me that RAM has known about this for some time.

From the noted case:
"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"

Not really any differant then the 5.7 then.You can use 87 in the 5.7,but they definitely run better on 89,and even better on 91.
Nobody buys a truck for gas savings,so you're going to have to suck it up,and buy better fuel. Who knows the truck might even get a bit better milege on 91,which will help offset the cost differances between the 2 fuels.

 

[joesstripclub]

Do you have e85 near you? My wife has a newer wrx and they love ethanol. The big tuners recommend adding 2 or 3 gallons e85 to a tank (16 gallons I think) if your tune seems to be unhappy from poor quality fuel. It adds octane and also burns cooler than gasoline. I've ran a 30% mixture without issue and I live right next to a station with e85 so its super easy for me. I wouldn't go crazy but try a couple gallons if you don't want to splurge for premium.

 

[steveni1234]

In addition to the new Ram, I have a BMW with the N55 engine, a three liter turbo that has always required premium 91 octane fuel. We never complained because the engine delivered better fuel economy (21 city, 27 highway) almost enough to make the price difference a wash. Higher octanes reduces engine temperature and improve fuel economy in addition to better performance. Bumping to 89 octane might be enough to clear the code and you should see a bump in MPG.

 

[turkeybird56]

My 2025 is in the shop for a P0300/0304 codes (misfire) with a steady CEL on the dash (960 miles on the odometer).


So far, the service advisor has said they're looking at it as a fueling issue related to octane and excessive heat. That is, 87octane from Costco and typical Phoenix weather do not play nice in the standard output Hurricane. They haven't called me back to pick it up, so the diagnosis may change, but I would appreciate some insight from the forum on what to expect.
Honestly, we would not have bought it had we known it would require premium fuel (the manual states 87 is fine) and this is the second visit to the shop in less than 1000miles (other issues were not related to the P030x codes); so I'm not looking to accept the "use premium gas during the summer" as a solution.

I'll keep the forum posted, if there is interest.

Any thoughts or advice?

DEFINITELY interested, since my Older son leased a 2025 a couple weeks ago, and is currently on a trip from NJ to FL, and back to NJ soon

 

[turkeybird56]

Do you have e85 near you? My wife has a newer wrx and they love ethanol. The big tuners recommend adding 2 or 3 gallons e85 to a tank (16 gallons I think) if your tune seems to be unhappy from poor quality fuel. It adds octane and also burns cooler than gasoline. I've ran a 30% mixture without issue and I live right next to a station with e85 so its super easy for me. I wouldn't go crazy but try a couple gallons if you don't want to splurge for premium.

PROBABLE really stupid questions? But than I am a BOIRD lol.

States this in the manual:
Do not use E-85 flex fuel or ethanol blends greater than 15% in this engine

SO, for all the informed/uninformed, what exactly is this saying? I know on my HEMI not FLEX capable.


I haven't used dat junk since like 2012 in US Govt vehicles, made for E 85. Is the SO/HO motors even E 85 capable? Hard to know since I do not have one and dang sure not want to "trot" over to a dealership to look, not want 10 ppl running at me trying to sell me a truck, LOL.

 

[jlgomez10]

Do you have e85 near you? My wife has a newer wrx and they love ethanol. The big tuners recommend adding 2 or 3 gallons e85 to a tank (16 gallons I think) if your tune seems to be unhappy from poor quality fuel. It adds octane and also burns cooler than gasoline. I've ran a 30% mixture without issue and I live right next to a station with e85 so its super easy for me. I wouldn't go crazy but try a couple gallons if you don't want to splurge for premium.

I don't think so. I think local ethanol blends max out at 10% at the typical gas station. My only option is going to be 91.

In addition to the new Ram, I have a BMW with the N55 engine, a three liter turbo that has always required premium 91 octane fuel. We never complained because the engine delivered better fuel economy (21 city, 27 highway) almost enough to make the price difference a wash. Higher octanes reduces engine temperature and improve fuel economy in addition to better performance. Bumping to 89 octane might be enough to clear the code and you should see a bump in MPG.

I suppose what rubs me the wrong way is that it was not marketed/advertised as a premium fuel engine. It makes me feel deceived as it was a very specific question I asked the sales person and researched on the SST SO. Unfortunately, 89 octane is not readily available in Arizona. I can either use 91 or try to make my own combo at the pump by adding half of each. Really my only option is 91.

Our other vehicles all require premium fuel (3 MINI Coopers and a Guzzi motorcycle) but I went into those with eyes open because the octane requirement was accurately published and the fuel economy was in the estimated 30mpg+ range. I'll keep an eye on the fuel economy and see how it works out over the next few tanks.

 

[turkeybird56]

I don't think so. I think local ethanol blends max out at 10% at the typical gas station. My only option is going to be 91.

I suppose what rubs me the wrong way is that it was not marketed/advertised as a premium fuel engine. It makes me feel deceived as it was a very specific question I asked the sales person and researched on the SST SO. Unfortunately, 89 octane is not readily available in Arizona. I can either use 91 or try to make my own combo at the pump by adding half of each. Really my only option is 91.

Our other vehicles all require premium fuel (3 MINI Coopers and a Guzzi motorcycle) but I went into those with eyes open because the octane requirement was accurately published and the fuel economy was in the estimated 30mpg+ range. I'll keep an eye on the fuel economy and see how it works out over the next few tanks.

U got a Motor Guzzi? Not seen one of them recently, been ages. I run a 2006 Honda GL 1800 Motor Trike. I run 89 in it even though the book says 87. I find 87 just not do well here in TX on my 06 MC. If I am taking a longer "ride", I run 93. The heat does take it's toll. (No 91 here, choices are 87,89,93)

 

[turkeybird56]

I don't think so. I think local ethanol blends max out at 10% at the typical gas station. My only option is going to be 91.

I suppose what rubs me the wrong way is that it was not marketed/advertised as a premium fuel engine. It makes me feel deceived as it was a very specific question I asked the sales person and researched on the SST SO. Unfortunately, 89 octane is not readily available in Arizona. I can either use 91 or try to make my own combo at the pump by adding half of each. Really my only option is 91.

Our other vehicles all require premium fuel (3 MINI Coopers and a Guzzi motorcycle) but I went into those with eyes open because the octane requirement was accurately published and the fuel economy was in the estimated 30mpg+ range. I'll keep an eye on the fuel economy and see how it works out over the next few tanks.

I talked to my son, who is currently on his 1st long trip with his 25 Bighorn. Before he left I told him to run higher octane fuel based on manual, heat and what some have been saying. Any way, he has run Midgrade entire trip, and reports 21 mpg on highway, says truck running great, no problems, and he is traveling the I 95 route.

 

[jlgomez10]

I run a 2006 Honda GL 1800 Motor Trike.

Very cool!

Mine’s a 2014 GRiSO 1200

 

[joesstripclub]

PROBABLE really stupid questions? But than I am a BOIRD lol.

States this in the manual:
Do not use E-85 flex fuel or ethanol blends greater than 15% in this engine

SO, for all the informed/uninformed, what exactly is this saying? I know on my HEMI not FLEX capable.


I haven't used dat junk since like 2012 in US Govt vehicles, made for E 85. Is the SO/HO motors even E 85 capable? Hard to know since I do not have one and dang sure not want to "trot" over to a dealership to look, not want 10 ppl running at me trying to sell me a truck, LOL.

I don't have any specific info on the new hurricane engines, but direct injection turbos seem to have some flexibility in the fuel system for ethanol blends. I suppose we will find out once people start tuning these engines. You definitely can't run straight E85 so you need either a blender pump or need to calculate how many gallons of E85 you can mix into your tank without going over X% blend required. I have heard of people running 50% ethanol or more in the wrx before they start to have fuel pump issues. On a stock WRX, tuners were getting an extra 100 wheel hp with 30% ethanol. "Junk" to most people but makes good power in the right application.

My other philosophy is that if they tell you something is rated for 15% ethanol for example, they are leaving a safety factor there. I ran 20 to 30% in my 2018 a few times and never had any issues with it besides the drop in mpg.

 

[turkeybird56]

Very cool!

Mine’s a 2014 GRiSO 1200
View attachment 549267

Haven't seen any of the MG's since I was in Europe, tho U saw more BMW's than anything else, since I was in Germany.

 

[turkeybird56]

I don't have any specific info on the new hurricane engines, but direct injection turbos seem to have some flexibility in the fuel system for ethanol blends. I suppose we will find out once people start tuning these engines. You definitely can't run straight E85 so you need either a blender pump or need to calculate how many gallons of E85 you can mix into your tank without going over X% blend required. I have heard of people running 50% ethanol or more in the wrx before they start to have fuel pump issues. On a stock WRX, tuners were getting an extra 100 wheel hp with 30% ethanol. "Junk" to most people but makes good power in the right application.

My other philosophy is that if they tell you something is rated for 15% ethanol for example, they are leaving a safety factor there. I ran 20 to 30% in my 2018 a few times and never had any issues with it besides the drop in mpg.

I think what the MANUAL is stating: to not use anything Higher than a 15% Ethanol Blend, like E 85, not percentage in tank. BUT no way I would run that friggin corn juice in my truck (Cannot run that crapola anyway, got a HEMI)< but if I had a 2025 RAM, on HECK!!!!! NO!!!!!

 

[Wild one]

No worries on running E85 in Canada,you can't buy it anywhere,lol.
There's one station in Calgary,and it's the only one i know of in Western Canada,there might be another 1 or 2 stations in Eastern Canada,but i'm not sure

 

[turkeybird56]

No worries on running E85 in Canada,you can't buy it anywhere,lol.
There's one station in Calgary,and it's the only one i know of in Western Canada,there might be another 1 or 2 stations in Eastern Canada,but i'm not sure

Me thinks dis BOIRD not make it to Canada any time at all.

 

[Wild one]

Me thinks dis BOIRD not make it to Canada any time at all.

Nicer weather up here in the summer then down south in Texas,lol. If you come this way,do it between the months of May and the end of Sept,good chance it won't snow to much in those months,lol

 

[turkeybird56]

lol. Been in Ft France’s in Sept 2001 and we momma and I left Tx in 90s. Was 33 there in AM. Froze tail feathers ofF.

Momma had aunt in Ft France’s across from International Falls and fam in WI.

 

[jimonqa]

I don't think so. I think local ethanol blends max out at 10% at the typical gas station. My only option is going to be 91.

I suppose what rubs me the wrong way is that it was not marketed/advertised as a premium fuel engine. It makes me feel deceived as it was a very specific question I asked the sales person and researched on the SST SO. Unfortunately, 89 octane is not readily available in Arizona. I can either use 91 or try to make my own combo at the pump by adding half of each. Really my only option is 91.

Our other vehicles all require premium fuel (3 MINI Coopers and a Guzzi motorcycle) but I went into those with eyes open because the octane requirement was accurately published and the fuel economy was in the estimated 30mpg+ range. I'll keep an eye on the fuel economy and see how it works out over the next few tanks.

I mix my own 89 octane at Costco. I fill the first half with Premium, then fill the remaining half with Regular. Leave the hose in the tank, and simply use your hand to lift the shutoff valve. Get thru the receipt & it resets as though you're a new customer. Tap your card, release the shutoff valve, then select your grade and finish.