Oil From Costco

Jaybeaux

Jaybeaux

Well-Known Member
Jan 3, 2016
2,051
Upper Potomac River
Boat Info
2006 Sea Ray 48
Naught On Call
Engines
Cummins QSC-540s with V-Drives
11 KW Onan Genset
While in Costco the other day, I saw that they were selling a Kirkland branded 15W40 Heavy Duty Diesel Oil. In previous years, they had sold Shell Rotella T4 15W40. I've been on the lookout for it this year, but haven't seen it. Then this Kirkland branded stuff shows up. Works out to $7.66/gallon compared to the Rotella T4 which is about $12.50 at WalMart.

Would you use it in your diesel engines? I may call Cummins to ask. If the spec is the spec, that's one thing. There could be some proprietary "additives" in the Shell that make it worth the extra $5/gallon.

Thoughts?

Jaybeaux
20200916_105532.jpg 20200916_105544.jpg
 
If you have a farm and fleet near you, they where offering good deals on the shell oil a week or two ago.
 
I wouldn't use it. How much are you going to save a year? $100? Not worth it to me.
 
Agreed with BMAC our boat had Napa trans filters on it at survey and the Cummins guy joked at how much the engines and trans cost and the op wasn’t at least using FLEETGUARD filters (shaking his head)
 
I've purchased Delo 400 or Rotella from Costco for years with great results. I've also been considering using the Kirklands 15W-40 as well for my MAN's. In August I had Blackstone run samples for my Engines, Transmissions, And Generator.

Kirkland's indicates they seem have the proper rating of CK-4 (see below) so I asked them (Blackstone) their opinion and received the following response:
"We've seen plenty samples of the Kirkland brand oil. They do a good a job of lubricating the engine."

Kirkland 15W-40 CK-4.jpg


Jury is still out but leaning towards Kirklands oil, but definitely using factory MAN filters.
 
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agree...although I use Valvoline blue premium/15W-40. It's has the Cummins approved stamp and can get it off Amazon as cheap as Rotella. I also do an oil analysis every year and it keeps it's viscosity properties pretty well.
 
Islandtime04 said:
agree...although I use Valvoline blue premium/15W-40. It's has the Cummins approved stamp and can get it off Amazon as cheap as Rotella. I also do an oil analysis every year and it keeps it's viscosity properties pretty well.
Click to expand...

FWIW, a Cummins certified tech I spoke with said that yes, the Valvoline is the official "recommended" oil but it was basically a marketing agreement. Any oil that meets the Cummins oil spec for the engine in question could be used.
 
Hmmmm. Rotella at $7.50 per gallon sounds too good to be true. Fishtale?
 
Maybe it’s the optics of it but if i told a potential buyer of our boat I religiously used Costco oil on the motors it may deter them a bit I know it would me.
My Blackstone samples of rotella come back with gleaming comentary from the tester so I’d like to keep them that way. Just the way I am.
 
Does the Costco oil have JASO MA certification like the shell rotella does? I use rotella T6 in all my motorcycles and quads. I also use it in the kubota diesel zero turn mower my friend let’s me use at the farm when the bush hog is too much. And I put it in my brothers tractor. Great oil! Maybe the Costco oil is the same oil under a different brand?
 
Costco, Sams, TSC, etc. buyers aren't looking for oil or lubrication ability when they buy oil.......they are looking to hit a price point. Said another way, do you really think Costo was looking for a high quality diesel oil when they loaded up on that $7.99/gal oil? Nope.....they were looking for a price leader for the diesel truck guys.

Saving 50% on my engine oil waves a huge red flag in my face and you won't find an empty Costco/Kirkland jug in the trash can behind my boat.
 
Frank’s right and we’ve had this discussion countless times over the years on other stuff, be it Mercury oil vs other brands, spark plugs, engine components, paint, etc. It still comes down to truck/car/motorcycle use is not the same as marine use.

Costco brands are usually pretty good and provide a good value proposition for general use. Would I buy Mobil 1 from Costco for my Porsches? yes. Would I put Costco oil in them? Not in a gagillion years. Would I buy Costco olive oil? Yes because it’s actually good and an extraordinary value. Do I run a fine dining gourmet restaurant? No.
 
I don’t understand why anyone would look so hard at saving a couple dollars on cheap oil.

Case in point, I buy Kendal synthetic for my Ford truck 5.4 v8. Why? Because ConocoPhillips manufactures Motorcraft oil for Ford. They also make Kendall and Phillips 66. Both of these have far superior additives package than Motorcraft oil. As soon as I started using Kendall I could hear the difference. I think one should buy the very best quality oil and lubricants possible. It’s cheap maintenance.
 
I agree with Frank. Costco certainly does not make it own oil. But for me, it's Rotella and Detriot filters only. Not going to chance saving a few bucks and risk $1,000s
 
If it is approved for the spec, not just meets the spec then it is fine to use and will provide good service for that use, as well as maintain warranty coverage. Name brand oils are good, but let’s face it, they too have to meet price point and investor expectations, so cost is important to them as well. I have been to a blending facility that filled house brand bottles, then 12 hours later were filling name brand bottles of oil. The point is, name brand oil was made at a contracted site the same as house brand. It is all about best cost production.
 
As a minimum, it all comes down to if it meets the manufacturers specification. As I was told by Performance Diesel (MAN engine supplier to Sea Ray), they just recommend an oil that meets MAN3275 as its a little higher spec than what was approved for my engines back in 2004. And that is what I will use.

Name brands that need to cover a marketing budget vs lower cost generic. Whether it be drugs or oil, at any given time we all voluntarily or involuntarily drink the Kool-Aid about something. Me included. Then we develop a history with something that works well and tend to develop an allegiance, that it's the best.

Whatever you choose to go with, make sure to follow up with sample tests from someone like Blackstone Labs.

If someone chooses to spend their hard earned money on a name brand that makes them sleep better at night or a generic, so be it.
 
Long ago I ran the maintenance department for a large company. We had standardized on on uniformity of equipment. The items were good quality; but spare components were very expensive. We were able over time to get some of the military specification numbers for the spare components and order them form suppliers. The cost saving was a factor of 5. They worked as well as the original components. Point is; if you change components (Oil) make sure it is the same as what is specified originally. If what we had replaced was not, the consequences would have been a very expensive error. You can start comparing MSDS and technical sheets of different oils to see if they read the same.
 
Brett H said:
As a minimum, it all comes down to if it meets the manufacturers specification. As I was told by Performance Diesel (MAN engine supplier to Sea Ray), they just recommend an oil that meets MAN3275 as its a little higher spec than what was approved for my engines back in 2004. And that is what I will use.

Name brands that need to cover a marketing budget vs lower cost generic. Whether it be drugs or oil, at any given time we all voluntarily or involuntarily drink the Kool-Aid about something. Me included. Then we develop a history with something that works well and tend to develop an allegiance, that it's the best.

Whatever you choose to go with, make sure to follow up with sample tests from someone like Blackstone Labs.

If someone chooses to spend their hard earned money on a name brand that makes them sleep better at night or a generic, so be it.
Click to expand...

Brett - The 5W40 Mobil Delvac ESP 1 is the only oil MAN specifically says meets their requirements. I’m supposed Performance Diesel didn’t say that. I don’t have the guts to try something else! Even if it is $40 a gallon. Is the Kirkland full synthetic?
 
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