The only Diesel rated oil around here is 15-40. It is very cold here, around 0 degrees. Would it be alright to run the 15-40, or should I go to a regular gasser oil like Citgo Super Guard 10-30, or other?

 

how cold is it? i use 5w30 in the winter .

 

It has been below 0 this week. Normally it has been in the 20s. I am in central Oregon. winters get cold here.I wanted to use diesel rated 10-30 but i cant find it anywhere.

 

cold oil isn't that big an issue. If it goes to 40w then the pump should still be able to circulate it, so your pressure will go up,but nothing else will change. Once the motor heats up it's a moot point anyway. If you were running a thicker oil that goes from 20-60 I'd worry about it, but not with the 40w max.