Originally Posted by Ggrvusa
We are the first owners of our '07 Revolution. We live in S FL and when we we drive our west, occasionally on cold mornings ( in the 40's) I've started the engine and the oil pressure stayed on zero. I stop the engine and upon restarting the pressure goes up. I started using the block heater and I still have the problem. I also often experience slow starts. I spoke with Cat and they said might be a sensor and recommended I switch to 10-30 oil. My Spartan service always puts in 15-40. The engine uses about a gallon of oil in about 6,000 miles. Cat said this is normal.
I am due for an oil change and thinking of putting in synthetic. I am concerned that my oil consumption may go up with the lighter synthetic, but maybe it will make for easier starts.
I cannot imagine that in the 40s would be any problem for a 15w- 40 oil. Hopefully someone from Alaska or Montana somewhere like that will chime in here. Going to the 10-30 will help out on cold mornings but will have a thinner viscosity oil when the engine warms up. I would not want that and like I said 15w should not be affected by 40 degree temps. I do not know if the cat engineers would recommend it but I use 5w-40 rotella synthetic in my duramax pickup and I like the way it works.
I also think there is a clue in your problem that the engine heater does not make a difference when you have it on and the engine warmed up. I would have the mechanics look at the sensor and keep using the oil you have been using if you like it. I use synthetic oil in all of my vehicles except the DP and that is because when they changed oil after I purchased it the shop used regular oil. If I start going to any very cold weather camping I will probably switch to the synthetic rotella like I have in my pickup