cetane rating

[mike.t]

I have an 09'3500 am I am trying to find out what Cetane rating Dodge/Ram/FCA wants me to run in my truck and do you people think/know it should be higher?
Thanks
Mike

 

[BarryG]

The epa mandates at least a cetane rating of 40 and leaves the rest to the states. Only California and Texas have specific requirements Cali requires 53 and Texas 48 other than that the other states no real telling what you will get except it will be at least 40. Diesel is not mandated to have the rating posted at the pump like octane is required for gasoline. Everything I have read on the subject is 45-55 is best anything beyond 60 is of no real additional benefit. With modern diesel trucks the engine doesn’t care nearly as much about the cetane as they used to as the timing can be much more controlled through multiple injection events per power stroke but the higher number does help with emissions as the higher number typically burns cleaner. However the higher number requires a higher quality of oil base to start with which means more expensive to start with or additives which are expensive as well so oil companies have no real interest in providing premium diesel fuel

 

[Ozymandias]

From my experience, with our European 51-cetan rated Diesel the Engine produce way less soot, runs smoother and mpg raises a little.
All compared to 2015 when i drove my RAM in the US and CA for 3 months.

 

[Jim W]

I have an 09'3500 am I am trying to find out what Cetane rating Dodge/Ram/FCA wants me to run in my truck and do you people think/know it should be higher?
Thanks
Mike

Hi, Mike; Welcome to the forum.

I have used the standard diesel fuel at truck stops for my needs an I have had no issues with any diesel fuel that I have purchased. The Cetane could run as low as 40 or as high as 50, what ever is in the under ground tanks at the station I have used. My truck is a 2008, Dodge 6.7L Cummins and I tow a 12,000 5th wheel trailer with this truck. I have been as far west as UT and as far east as ME. My wife uses the diesel fuel that a local supermarket chain sells in her VW TDI with no issues.
If you are worried and you want to pay the extra expense for a Cetane Boost you can use POWER SERVICE Diesel Supplement. I have attached a link to their site. https://powerservice.com/ I do use this in the winter months just as an added protection against gelling the fuel, not needed but I do use it.

 

[AH64ID]

Diesel refined with higher Cetane ends up with lower BTU’s and lower peak combustion pressure. Higher Cetane should reduce fuel economy at higher loads, but at lower loads the higher Cetane can increase combustion efficiency and thus a slight increase in mileage.

The biggest benefits to higher Cetane are low temp/low load combustion, starting, and high rpm operation (think small diesels that rev high, and are all over Europe... hence their higher Cetane requirement)

I use a Cetane boost occasionally when I know I’ll be at a very low load for a long time, such as elk hunting in the fall. Otherwise I don’t use it much.

On my stock motor with Smarty Jr standard tunes Cetane boost would make my motor knock something fierce. I didn’t use it after I figured that out. With my current motor, and tuning I can run it with no negative side effects.