whats the best synthetic oil to use in the winter time in my 2003 dodge ram 2500 diesel, i do not tow anything and make frequent short trips about 12 miles a day. i live in central virginia were it does get in the single digit temps from time to time, whats the best brand and weight to use????

 

I'm just running 15-40.

Where are you located at?

 

Shell Rotella Synthetic, can be found at your local Wal-Mart, has a 5w-40 rating.

 

Delvac 1/Mobil 1 Truck and Suv 5w40 is good to something like -46F . Should have ya covered =] The rotella synthetic isn't a full synthetic, it's a group 3 petroleum based 'synthetic' . It is attractively priced though. Truck and Suv is available at most walmarts and auto parts stores..look for the yellow cap.

 

I have 14,000 miles on my CTD, at about 18k I am going to change to either Delvac 1 or the Exxon Syn (whatever is available at my Cummins Dealer) and change oil at 12k.

 

I use Amsoil 15w-40 year round with Stratapore filters, every 7500 miles. No problems. This oil will remain fluid/Pour point is -46. It doesn't get that cold in Virginia or Texas!

Delvac 1 (5w-40) can be had at Wallyworld under the Mobil 1 Truck & Suv 4x4 label with the yellow cap. Great oil too! Pour Point, ēC, ASTM D 97 -45 .

you couldn't go wrong with either of them!

 

If I lived somewhere warmer than Cleveland, I would use Amsoil 15w40. However, in temps below 10F, the 15w40 really starts to lose out in flow compared to the 5w40's like delvac 1. While the amsoil will POUR at -45F, it's still way way thicker than d1 at the same temp. At one point I had some date on the comparative viscosities at 10F, and up until that point the 15w40 Amsoil and D1 were very similar. In VA you probably can get away with running either. Here we get a few weeks below 10F each winter.