The flier said that it was rated for diesels and it was the CI-4 rating. I checked everything out comparing it to the 15W40 and the only differnce that I saw was in the weight and the names. The 15W40 that I am using is the heavy duty diesel and marine oil, while the label for the 3000 series is a gas and diesel oil. Not sure if there is a any differnce, just wanted to know if anyone is running this in there truck.

Even if the dealer say that running oil for extended times isn't good, if you do a oil test to see how many particulates are in it and it is good who is to say that the oil is bad? The dealers are just going with what is in the user manuals. The only thing that I can think of that might be a problem is the build up of sulfur in the oil, and a oil test should be testing for this. Hey, if it is going to be easier on the engine and my pocket book I all for it.

 

Now that you mention it, I see on the Amsoil site that it is CI-4 rated, I'll go see if my stuff is too. I bought it a couple years ago, so they may have changed it. If it is CI-4 then I'll just keep it for my CTD rather than change it one last time in the Talon (going up for auction tomorrow). I don't think the MB would care for 5w30 as is, it was rated for 15w40 and I'm already running a 5w40 in it.

 

I had over 80,000 miles on AMSOIL before changing it. My truck is set up with the dual by-pass filter system. The by-pass filter was changed once a year, the spin on every six months. Every three months I was taking a sample and sending it in. One of the numbers to pay close attention to is the TBN, total base number. As it goes down the oil is not as lubricating. It has more than paid for itself in the four years I've been using it. Will continue to use it as long as my sample comes back good.

 

TBN is directly related to the acidity of the oil, an oil with a higher TBN has more anti acidity package in the oil to help fight sulphur/ combustion acids.

 

How does viscosity hold up with the 15w-40? Does it thicken up like the 5w-30 turned to 50 weight in the gasser? Just curious...
Just a FWIW, Amsoil "rates" their own oil as CI-4. It's not API "certified" CI-4. CI-4 is an API ceritification and Amsoil wouldn't pass the test for certification because of the high additive package. So it's not CI-4 certified. I'm sure it's good stuff but I have a hard time with the deception part of it. Kinda like "exceeds ATF+4". How? It either meets the requirements set forth by DC or it doesn't. There is no "exceeding" the requirements. Too much of this or too little of that in the recipe both fall short of DC's requirements and unless the recipe matches DC's ATF+4, it is not ATF+4. It's something else.
Ok, now I feel better.

 

Amsoil fails to meet the API certification, for some reason Amsoil will not present their oil for this API certification test.

Now if you read your owners manual or look at the oil cap of most all engines it clearly states to use API certified oil that meet certain specs. Failing to meet these API specs could result in your engine warranty being voided.

Amsoil does not meet those API specs. Amsoil only claims their oils meet those specs.

I use Royal Purple in my engines, well I will in my Cummins after it passes 15,000 miles but I use it in my other engines.

The Royal Purple is API certified for the CI-4 specs.

Makes me wonder what Amsoil is afraid of to present their best oil to API for testing.

Now you could also run that 49 cent a quart quickie mart oil in your engine and as long as you change the oil every 3000 miles nothing would happen to your engine, but do you really want to use that cheap 49 cent a quart oil? Would you really want to use non-certified Amsoil as well?

Not me.

I will stick with API Certified Royal Purple oils.

 

That is exactly how I feel about Amsoil too Hannibal, they discredit themselves with all this exceeding claims but without actually testing stuff. My "new" truck (anyone wanna buy a Talon? ) will probably be just Delvac / Redline oils.