Just read a thread on the 6.0 PSD sight,about oils,
and was wondering what the general consensus is over here.
SYN or CONVENTIONAL oil?
Is it worth the extra cost? Does it extend oil changes?
Does it extend engine life? Anyone with history?

Thanks, Howard

 

I like synthetic, I have no reason too. I use Royal Purple now, but I have tried Quaker state, valvoline and mobile 1. Mobile 1 is nice, I noticed the engine felt tighter then with valvoline, and the same when I went from quaker state to valvoline. I get a good deal on Royal Purple so that's what I use.

 

Synthetics will help starting in cold weather. They can extend the drain intervals, but an oil analysis is recommended. Several have also commented that the diesel motor seems to be smoother or quieter with the synthetic.

I've only run the regular stuff in my truck, and after 258,000 miles this is what it looked like under my valve covers with the stock injectors


I think I'll just stick with the regular stuff.