Any company will charge for analysis and there are several good ones. I haven't used any besides AMSOIL yet, but would like to try Blackstone Labs someday. They all run about the same, ranging from $15 to $25 depending on whether postage is included or not. ONe thing to watch for is some companies don't include a TBN result. AMSOIL does include, but with others you want to be sure you are getting the TBN. It may cost extra, but it's an important determinant of how far you can go on the oil.

Here's our brochure that goes over some of the basics.
http://www.amsoil.com/lit/g2047.pdf
I do know aviation is a whole other ballgame. AMSOIL does not do analysis for aircraft.
Heath

Actually with the 15-40 premium diesel oil (blue label bottle) and the EA extended life filter you can run both to 25K before changing. Heath should have the info from Amsoil on that. I've run this oil in my last 3 Dmax's with good results. Now that the EA filters are out I've done two oil/filter changes on the new truck with good oil analysis. I usually get 22K out of mine before analysis says I have to change but my truck races, tows, and gets thrashed on the street so mine comes up a little short. :up:

That's correct. With the Ea filters, it's 15000 or one year in severe conditions(towing, stop and go, etc.) or 25000/1year for normal use. If using other aftermarket filters, the oil will still go the distance, but they need to be changed around 7500 miles. The Ea just save the hassle of having to do that, and it filters a little better:)
OA, as mentioned, can allow you to go farther.

Just an FYI for those that are interested...I do an oil analysis every 8K and then at 22K to make sure I'm good. And like Heath said, make sure that whoever you use gives you the TBN on the oil. Without that information you just wasting money on something you dont know how to read. I use Oil Analyzers Inc and they not only include the breakdown of each component in the oil but the TBN also. They also track my history and send me a graphical chart at every sampling.

FYI, Amsoil's 5w40 is made for the new 6.7L EPA smoged up, DPF engines so you should use either their 15 w or 5w oil. My self I run Amsoil 5w30 HDD oil and like it a lot. I've talked to other CTD owners in So Cal who also use Amsoil 5w30 HDD oil and it hold up just as good as 15w40. Also I think I get better fuel mileage by using 5w30 oil verse 15w40 oil. The 5w30 HDD may cost a bit more then 15w40 oil but I feel it all works out in the end with me getting better fuel mileage.

My $0.02

Yup.. I am running the 15w40HD with the EAO80 Filter, and its about time for the first sample on it. I plan on running it for AT LEAST 25k miles... As long as the analysis says its ok to do so..... For me, its worth it. I HATE changing oil, and I have to do it outside, in the cold, so the fewest amount of changes I can do, the better.
Scott