Diesel oil ?

[fliesitdies]

Any opinions about the kirkland 15-40 diesel oil versus Delo 15-40 for a 2007 classic duramax.
Thanks Fliesitdies

[EnglishSetter]

I use it in my truck and boat (both 5.9 Cummins).

I'm sure you can find a discussion on "bob is the oil guy".

[Dan-o]

Some folks claim the Kirkland oil is actually better:

Lots of youtube videos on Kirkland oil.
It seems to get good ratings on most of the test videos.

I've got a 2006 Duramax.   I use it.
I personally think oil change interval is more important.
I change my oil at 4K intervals.
N o issues so far, but I only have like 140K on my motor.

[metlhead]

No issues at all in my diesel engines using value brands. They exceed requirements. Buy more at lower price will let you shorten the intervals of desired.

[Boss .300 winmag]

It’s the same oil.

As of early 2025, Kirkland Signature Heavy Duty Diesel 15W-40 oil is manufactured and packaged by Chevron. This marks a shift from their previous supplier, Warren Distribution, to a synthetic blend formula sold in 3-gallon packs.Manufacturer: ChevronType: Synthetic Blend API CK-4/SNPrevious Supplier: Warren Distribution (who produces [Mag 1] and [Super Tech])The product is commonly identified as a high-value alternative, with some users speculating it is a private-labeled version of [Chevron Delo].