Dang it - I was just at Wally World with a honey-do list from the wifey.... Thanks bluebull - I'll check that out. I'm assuming the Mobil stuff is CI-4 rated, correct?

 

If you look on the back of that Mobil 1 jug, notice that there are API Cert.#'s missing that all diesel oils have, that auto oils don't. I've talked extensively w/a diesel mechanic that said auto oil is fine to run in an emergency, but cautioned that prolonged use of it will leed to major ash deposits in the cylinder heads. All diesels are made to burn a certain amount of oil and that is why you have the different cert.#'s between the two. Neerly half of my family is in the long/short haul comercial transport buisness, and none of them would even think to run automotive oil in their Class-A trucks regardless of how much cheaper it is.

 

You might want to try Amsoil 15-40w, alot of people don't like it because of the price, but if you find a fair dealer its not bad at all. I use it and won't ever go back to regular. As of smell, i never thought any oil smelt like anything really, but gear oil has a smell to it, just might that i'm so used to the stench of a machine shop . Plus amsoil is rated for 15k oil changes with one filter change, you can put even more on if u want too.
The part i like is that at -20*F its still a liquid unlike good old rotella which gets a little clumpy when its cold. just my .02

 

If your looking at mobil 1 yes your right, If your looking at Mobil truck & SUV it's the same as Mobil Delvac 1 and they are both group IV synthetic DIESEL oils, which by the way can be run in any gas engine.

Diesel oils are designated with a C, CI-4+ being the latest.
Gas oils are designated with a S, SM being the latest.
CI-4 without the + is fine to run in the Cummins engine, the + was formulated for ford and chevy with EGR systems.

I beleave Mobil truck & SUV 5-40 will flow down to -64F, **** cold is all I know.

 

We put rotella in almost everything i do a service on at work, and i have never noticed a smell.

I just changed the oil in my truck and filled it with this :



And i have not noticed any smell.

 

I don't know about -64, but I was able to start my truck at -20 without plugging it in last year running the Truck and SUV. Make sure you have the Truck and SUV 5/40, it has the API CI-4 rating.