What kind of oil ?

[f250power]

Right now I'm using Rotella 15-40 in my 2003 7.3. wondering if switching to synthetic would be beneficial. It's got about 49000 miles and no leaks, what's your opinions ?

[bigd4me2]

If you start your truck in very cold weather synthetic is the way to go! many run synthetic in winter/dino in the summer.
i'm in a warm climate for now, so i'm happy with dino! i like delo 15/40, next mobile delvac 15/40, and rotella 15/40 like you are using. for synthetics i like mobil, and rotella 5-40. IH suggests delo 15/40