Yeah, but not all of them meet the CJ-4 standard for low-ash compression ignition oil, which is a requirement for the 6.4.

I was told that changing the oil before the 10,000 miles was a big waste of money ??? I changed it at 5,000 miles, I just don't feel comfortable going over 5,000 miles. I'm old-fashion & like doing it every 4,000 miles

Can't screw over on the warranty that way.

I change my oil every 3000 miles/5000km, regardless of usage.

I don't think the quality or longevity of the additive packages that are added to the oil are suitable for use for extended periods like that.

When it's something as cheap as an oil change....might as well up the frequency.

Then again, I do my fuel filters every 10,000km/6000mi too...so...

I'm going to keep changing the oil every 5,000 miles, if I go syn rotella, then I will change the oil at 10,000 miles:ok1:

Probably wouldn't hurt to do an oil analysis every once in a while just to make sure nothing is wearing too fast or fuel getting into the oil or that kind of thing. Good preventative maintenance.

There's gonna be fuel in the oil on a 6.4 :)

I have drained upwards of 20qt (total fuel and oil mixture) out of a 6.4 PSD.

Regen beats up on the fuel in oil situation, BAD.

Really? How much does the 6.4 hold for oil?

I think the manual specs out around 15 qt, I usually set 'em around 14 and ship it. (13.5 Liters) because they ALL gain level, so I'd like to leave a little room. I set it up so its about 1/3 of the way up the crosshatch pattern on the stick.

That's just wrong, Why would FORD tell us to change the oil every 10K, if there will be fuel in the oil:argh: