LEAD UP STORY:
So here is the deal. I have been using Amsoil 0W-20 Grade 4 Full Synthetic oil in my car(s) for the past 4+ years. Like any normal person, I would do regular oil changes every 5-8000 km, as described by the service manual.
So when my last oil change was due, I naturally called up my contact at Amsoil to order more oil. He then questioned me as to why I was changing my oil so soon, and naturally I reply “My oil change is due” he then says “You know Amsoil is good for 24,000 MILES right?” I of course say “Ya bullshit” He then goes into his sales pitch, I then look online and at the bottles and ya, Amsoil recommends servicing every 24,000 MILES which equals 38,624.256 KILOMETERS.
Who in their right mind is going to leave their oil in their car for a FULL YEAR?!
I am.
I got an oil analysis done on my last oil change, which equalled to about 8,000 KM. This is what was shown.
I had no idea how to read this, and given that engineers probably built their website, they have no idea how to dumb this type of thing down for us regular folk 
So after a few phone calls to Staveley Services here in Edmonton, I got some answers.
I wanted a sample test that was very critical, to compare mine with. He couldn’t email me anything so he gave me a bunch of numbers from some samples that were critical.
Basically if my #s are anywhere near these numbers below, I need to do an oil change immediately.
Iron - 250
Copper - 60
Aluminum - 25
Sodium - 50
Potassium - 50
Tin - 20
Chromium - 20
Nickel - 5
Silver - 5
Derilic Dust - 50
Now you can see that my numbers are no where near the critical numbers listed. I plan on putting this Amsoil Guarantee to the test over the next year or two. I will be stretching my current oil change out to about 12,000 - 15,000 km and then doing another oil analysis. If my numbers are still good, I will stretch it out to 20,000 km and then do another change and analysis.
CAR BIO & PRODUCTS USED
2008 Nissan Sentra 2.0L with approx 35,500 km
Oil - 0W-20 Amsoil Full Synthetic
Amsoil Oil filter - EA012
I am also using Powerup NNL-690 Oil additive for Gas engines with every oil change.
Next update in about 4-5 months If this does work, and the numbers won’t lie, I will never use another oil product ever in any of my vehicles.