Just learning about diesels, what is the best motor oil to use. I have an 04 Crew Cab 2500 with an LB7.

pretty much any 15w-40 or 5w-40 synthetic

I use AMSOIL and Mobil 1.

Its up to you wether you want to you use synthetic, or petroleum.

If you tow heavy, or run a chip I would reccomend a synthetic

But for everyday stock use, petroleum is fine

doesn't matter too much what brand you use as long as it's properly rated for diesel use and it's changed regularily. However, that being said, synthetic's with their higher temperature durability will probably be the best over the long run for the turbo.

Filtration is also very important. Use a good quality filter such as the Mobil 1, genuine AC Delco or Baldwin.

pretty much any 15w-40 or 5w-40 synthetic

I use AMSOIL and Mobil 1.

Its up to you wether you want to you use synthetic, or petroleum.

If you tow heavy, or run a chip I would reccomend a synthetic

But for everyday stock use, petroleum is fine

The ref. to Mobil 1 above is either "Mobil 1 Truck and SUV" or "Mobil Delvac 1", I'm not sure which but it isn't regular Mobil 1.

Others are Shell Rotella T, Shell Rotella T Synthetic, Mobil 1300 Super, Chevron Delo, Amsoil HDD & Marine and Amsoil HDD Series 3000. The point is that you should use an oil that is rated for diesels and with the correct API specifications, which doesn't necessarily imply that it has the API seal as Amsoil doesn't.

Where's the best/lowest price I can get AMSOIL ???

If your going to use Amsoil regularly the best thing to do is find a local dealer and sign up to be a prefered customer. This will allow you to get discounts on all Amsoil products. I've been using Amsoil in my 2 jet-skiis for the last 5 years and it works well, but it is still a bit expensive when compared to regular brands of oil. Good luck.

How about Quaker State I have always used this in my Gasser now that I am going to a Diesel I wonder if they make a good oil for them?

How about Quaker State I have always used this in my Gasser now that I am going to a Diesel I wonder if they make a good oil for them?


I bet your gasser had alot of varnish inside I have seen what penzoil and quaker can do to a motor by personal experience. Pull a valve cover and there will be some type of film or varnish. I used valvoline and it cleaned up other oils deposits before they had got to bad. Now I have a diesel and I use Mobil 1.

In addition to the others mentioned ,Valvoline Premium Blue 15-40 is an excellent oil and Schaeffers 7000 Blended oil is a good choice. I use the latter because not only is it a blend but it has moly in it and I believe, provides better protection for the tubine. Schaeffers is a little pricey. Recommend you consider a add on fuel filter also. Highly recommend the kit put out by NICKTANE, it features a large 2 micron filter from Catapillar.

Actually the oil that came in the mail today is the :
AMSOIL Synthetic 15W-40 Heavy Duty Diesel & Marine Motor Oil.

Is this ok to use in my 2003 Duramax HD 4x4 ??????

That Amsoil 15w-40 is what I use in my Dmax and both my gasser rat motors. Couldn't beleve how clean the gasser truck motor was when I rebuilt it at 140k. I use to (probably won't with the Dmax cauz of soot) use the take out oil from the truck for the lawn mower, it's nearly 20 years old and still runs fine. :ro)

That is the right oil. That's exactly what I use in my 02.

thanks guys.
I think I will use AMSOil from now on.

I only use Royal purple 15 40 I busted my oil pan when offroading and made it 5 miles back to my camp. fixed the pan added oil and drove 750 miles back home. I will never use anything else

what about oil filter?
what do you guys recomend?

Actually the oil that came in the mail today is the :
AMSOIL Synthetic 15W-40 Heavy Duty Diesel & Marine Motor Oil.

Is this ok to use in my 2003 Duramax HD 4x4 ??????

Ace,

That is what you should use, IMO.

Idahofox

Most people who view anything as more of a hobby/obsession than a practical cost to value issue love to do more and spend more on their hobby! The bottom line is it's hard to know if a product is better, or we've just fallen for a marketing approach to justify a much higher price! In terms of motor oil, I don't believe there is a substantial difference between the super duper hyped oils and oils with the same API service ratings! Walmart Super Tech oil (Why, you can't be serious!) meets the requirements of Allison, Cummins, Mack, etc.! Paying less for oil allows me to change it a shorter intervals which I think protects your engine more than buying super duper highly advertised and hyped oils! The chemical pollutants that pass by the best of rings are the real causes of oil deterioration! They collect in any and all oils even if you pay $100. per quart! Without controlled testing, there are too many variables to know what causes your truck to run or last better than mine! We all have to just make our "best guesses" on theory and common sense, but don't fall for the hype of the company that makes the fishing lure! Sometimes you can't even trust the fish! The best day I ever had fishing I lost my bait and caught a limit of trout with Fritos on a bare hook! When they biting they're biting, when they're not, they're not!

Be happy, and make your "Good ole boy, common man, multimillionaire oil man, friend of the common man, the President get his oil company buddies and Saudi friends to stop gouging us for diesel fuel! Watch the oil company profits for the true story!