Diesel oil

[Sandybar]

I’ve had gas rigs up until now, first diesel ever owned. Going to need an oil change soon, my question is conventional oil or synthetic oil? Is Synthetic worth the xtra price?

Thanks in advance

[Grumpy]

Rotella, by Shell would be my choice.

[PaulB12]

Syn is fine, but in my case pricey, 10 qts!! 7.3 powerstroke. I run the Rotella.

PaulB12

[Midnightmoon]

What vehicle do you own? That makes a difference in some cases. Your owners manual should have a more detailed description of their recommendations.

Most off the shelf diesel oils now meet API CK-4 specs and should be fine for modern emission controlled diesels.

[Old and soft]

That's news. My 7.3 takes 15 quarts. Only rotella every 5k. Fuel filter every 10 k, only Motorcraft.

[PaulB12]

Originally Posted by Old and soft

That's news. My 7.3 takes 15 quarts. Only rotella every 5k. Fuel filter every 10 k, only Motorcraft.

Woops! My bad, 15 it is...
PaulB12

[Sandybar]

I have a 2020 Chevy Duramax.

[Bookemdanno]

I just purchased the Costco Brand (Kirkland) synthetic diesel motor oil. I'm due to change the oil next month. I was using the stealership to do my oil changes, but I ran out of the "free" ones. I figure if it has the Costco name on it, it can't be all that bad...and it's probably made my Mobil 1, Rotella, or some other top brand??

[Lake Huron]

Cummins should run Valvoline Permium Blue, Fords were always Rotella, and the Dmax was Delvac 1300. Nowadays they are all about the same and the question is dino oil or synthetic. AND filtration.
Me personally, I run synthetic and run Amsoil. I also installed a dual filter remote bypass filter system. Better filtration for these poor emission choked engines. I'm not one of these guys that'll stand on their soapbox and swear up and down about Amsoil, but I will say because it's a synthetic, the synthetic oils hold up and protect better than conventional oils. If you plan on keeping it a while, protect your investment and spend a little now on good oil and a good filter instead of a lot later in repairs and rebuilds.

[CAG]

Originally Posted by Sandybar

I have a 2020 Chevy Duramax.

Check your user's manual. It will give you the weight for the temp range you live in. Generally for diesels it is 15W40 for overall use. I don't know about the new Duramax engine but mine took 10 qts and I ran (still run) Amsoil synthetic in all my vehicles and have for 15 years or more.



Someone mentioned changing the filter with every other oil change and I have to ask why leave a quart or more of dirty oil in the system when you change? Filters are not that expensive.

[Old and soft]

FUEL filter every 10k.

[Colorado]

I’ve been running Triax 5w/40 in my 7.3L for the last 4 years. I had been running Rotella just never like how the truck ran. However, I tried the Triax and it’s a completely different truck...idles smoother, starts quicker in the cold. The only drawback is you need to order it online. Amazon offers a subscription so I typically just get it delivered every 5 months. Typically I get it from Amazon or EBay...

I get an oil analysis from Blackstone Labs at least 2-3 year and everyone has shown the oil is performing exceptionally well.

https://www.amazon.com/dp/B071RFB15F..._HDUWFbXZJ5HZK


https://www.blackstone-labs.com/abou...-oil-analysis/

[CAG]

Originally Posted by Old and soft

FUEL filter every 10k.

OK, but think of this. Every Blackstone I ever had done said that the silicon level was higher in my Duramax. That is because I live in a very dusty environment. The desert. So I change my oil, filter and air filter more often than is required. BTW Silicon is sand. That is running around in your cylinders.



You are leaving a quart or more of dirty (who knows what is in it) oil in your vehicle at oil changes. That is extra, what ever gunk, running around in the oil that you changed.



Amsoil, on the other hand recommends that the filter be changed every 10K or so if you are running the extended oil change program. So you change oil, and then at 10K you change the filter, add a quart of new oil, and run another 10K or more. You should also be doing Blackstone tests (or some other company) to see what your oil actually looks like.



Leaving a quart or more of dirty oil at an oil change defeats the purpose of the oil change.

[Lake Huron]

I dont know about the new L5P engine but the LML's have an oil pan that leaves a quart of dirty oil behind. There is a hump in the middle of the oil pan and that hump traps old oil in the front half of the pan. The only way to get it out is to suck it out with a pump and tube up thru the drain plug, OR replace the lower oil pan with a flat bottom pan. Lifting the front end up will get out about 10oz, 12 if you're lucky. Even doing that there is still some oil in the upper oil pan you'll never get out.

[Seann45]

My '04 D-max with 400,000+ on it has on had Rotella full synthetic in it....

[curver900]

yea an oil thread!! wooo hooo!!!!!!!

if you live up north where it gets cold then you need to go with synthetic in the winter... but cold is relative... the manual states below zero you need synthetic..

I run what ever has the best deal at the local fleetfarm with rebates..
conv during the summer and synthetic in the winter..
change the fuel filter when the dic says 30% left... that was advice from the diesel mechanic at the dealership...
any oil that meets or exceeds the standard will be just fine... free oil changes from the dealer use conv 15-40w mobil oil... and that is what they use if you pay to have them do it... to do synthetic will cost you an extra benjamin.. yikes!

[LuckyDuck]

Another 7.3 here. Ran Delo 400 LE dino since birth until they changed the formulation about a year ago. Now it’s Rotella T4, 15w40. Our climate is mild and dino oil is expensive enough for 15 quarts. Runs great and no leaks. Oil change and new Motorcraft filter every 4K-5k miles.

[mokurt]

I have been using Chevron Delo for years.

[CAG]

Something that no one mentions is there are tests done on most oil used in vehicles. You might be surprised how your oil of choice did on shear and other tests.

And yes, the oil thread. Which oil, which tire, which wax? Im betting there are several hundred “oil threads? Someone else will be asking on a new thread next week

[TCNashville]

Originally Posted by Sandybar

I’ve had gas rigs up until now, first diesel ever owned. Going to need an oil change soon, my question is conventional oil or synthetic oil? Is Synthetic worth the xtra price?

Thanks in advance

Pop the hood and look at the oil cap. That's the weight you should be running as it usually covers the largest spectrum of outside temperature ranges. You can run either dino or synthetic. If you plan on short interval changes, the synthetic is overkill. Your owners manual is your friend as there will be a "severe service" change interval as well if applicable.