Ok, at this risk of sounding like a novice (which I suppose I am), I have a minor dilema on which oil to buy. I have a '05 3/4 ton with a 6.0 PSD. I have about 8000 mi. on the truck, the last 5000 I've had M1 truck and SUV 5w-40 syn oil in the motor. I'd like to run syn oil, just for my own peace of mind, but I also want to run an oil with the CI4 plus rating. The M1 is just CI4. Rotella T syn would be my first choice, as Walmart supposedly carries it but both supercenters near where I live are both out of stock... I'd like some different opinions about which way I should go... Should I stick with the M1, switch to conventional rotella 15w40, or go someother way? I want to use something I can reliably get my hands on at the local store everytime I walk in the door, too. I know there are a lot of arguments on dino vs. syn oil, and I'm not trying to start that debate again. I simply prefer the syn because of the easier starting. I have a friend with a cummins powered dodge that has a hell of a time starting in the winter around here (Iowa) and his diesel mechanic claims its simply due to the 15w40 weight oil being too thick and over time it weakens the starter. Personally I don't know if he just needs new batteries or thats the real cause. Thanks for taking the time to read my rambling. Any replies would be greatly appreciated.

Thanks,
Kurt

 

the mobil T & SUV is identical to the delvac 1. both oils meet the same CI-4+ spec, mobil says they cannot put the + on the bottle due to them not paying to have it tested. they see no need to do so with that oil as it may draw away from the delvac oil. both oils are identical just different prices.

 

You could just buy Delvac 1 in gallons (isn't the SUV stuff in quarts?) and be done with it...

 

oppy the t&suv comes in 5 quart bottles for 22.25 at walmart. delvac is 26.99 at napa for a gallon.

 

Due to the long brake in period on a diesel I would run conventional oil for the first 15000 miles.I have seen Rotella T 5/30 or 5/40,can't remember which,at Wallmart. Larry

 

Thanks for the input guys. If the M1 is the same as the delvac, I can get a hold of it at walmart for $20.17 for a 5 qt jug. Never seems to be a shortage.