My brother spoke to a new Dodge owner who said the only oil he's allowed (warranty) to run is 15-40. I don't do much reading about the 07.5- 08 trucks. I couldn't believe that's true- is it??

 

The 6.7L Cummins requires CJ-4 (low ash) oil. I have found 15W-40 and 5W-40 available in CJ-4 rated oil.

 

So- it requires the CJ4 rating? Also- is that 5-40 synthetic?

 

The only 5W I am aware of is synthetic. My owners manual recommends a viscosity below 15w (I think it was 5w) in lower temps and requires it, or the use of synthetic at really cold temps.

 

Yes, CJ-4 is required. This is discussed in the owner's DVD. The low ash oil is required because of the DPF emissions system. The 5W-40 oil I found was Valvoline Premium Blue (Extreme) synthetic. I believe Valvoline Premium Blue 15W-40 is what Cummins uses from the factory.

5W-40 synthetic is available from other manufactures as well.

 

Thanks! I'm guessing that other brands will eventually be rated CJ-4. I'm using ESSO(Exon)) 0-40 synthetic right now in my 05.

 

Is Rotella rated as CJ4?

That is all I've been using in my vehicles for a long time with good success.

ben

 

Rotella Synthetic is not CJ-4 compliant. Regular Dino Rotella is CJ-4.

 

Cool. I use the regular dino stuff.

ben