Diesel oil in gasoline cars

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Looking at a sale flyer from a local parts store . Noticed the " diesel engine oils " . What would happen if you ran it in a gasoline engine ?

Thanks ,
 
There is a starburst on the container. It will have a CJ-4 or CK-4 rating for diesel.

It will also have a /SM or /SN rating if it is compatible for gasoline engines. (Example: CK-4/SN)

The new CK-4/SN oils promise superior lubrication to the older CJ-4/SM rated oils.

It depends on your specific manufacturer recommendation but typically HDEO (heavy diesel engine oils) are fine for gasoline engines except they are of higher viscosity than gasoline motor oils nowadays which are trending towards 0W-20's for fuel economy.
 
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It needs to have a Gasoline engine rating : SL/SM/SN...
Many people run Disesl a.k.a HDEO's ( Heavy Duty engine oils ) such as Shell Rotella or Chevron Delo 400 in older flat tappet camshaft engines due to their higher ZDDP concentration, they also usually are higher in sulphated ash content.
If you have a modern roller camshaft engine there is really no benefit against a quality PCMO ( Passenger car motor oil ).
 
Originally Posted By: WyrTwister
What would happen if you ran it in a gasoline engine ?

Thanks ,


Nothing would happen...you will be driving your car as before
smile.gif
 
I mistakenly called HDEO by the wrong name...it is an abbreviation for Heavy Duty Engine Oils.

Sorry, it was late at night.
 
Nothing will happen. Thousands and thousands of people do this. Google "turbo Subaru oil" and you will see most people run Rotella T6.
 
Since diesel oils are strong on soot dispersancy, it might not be a bad idea to pick an oil rated for diesel engines in gasoline engines. (Of course make sure it says SN or SM amongst all the diesel engine ratings.)
 
The biggest problem with running diesel oil in cars and pickups is the phosphorus content is to high. It may kill the cats. We had this issue in our fleet when we tried to run 15w-40 in all our vehicles, high cat failures. When we went to running the proper spec. oil in every thing, cat failures when way down.
Just saying.........
I know that most Chevron and most Mobil diesel oils have lower Phosphorus amounts. They also carry the SN rating. A easy way to check is if Ford approved it for their 6.7L, I would not put it in a new car engine.

Just saying........
 
I've been using Chevron Delo 400 15W-40 in my old Studebaker V8 engines since 1980 when we started operating our trucks. As long as the oil has a gas engine rating, it's good to use in both gasoline and diesel engines.
 
Originally Posted By: RLS
The biggest problem with running diesel oil in cars and pickups is the phosphorus content is to high. It may kill the cats. We had this issue in our fleet when we tried to run 15w-40 in all our vehicles, high cat failures. When we went to running the proper spec. oil in every thing, cat failures when way down.
Just saying.........
I know that most Chevron and most Mobil diesel oils have lower Phosphorus amounts. They also carry the SN rating. A easy way to check is if Ford approved it for their 6.7L, I would not put it in a new car engine.

Just saying........


What he said.
 
As long as it has the SM/SN rating it should be Cat safe.
With so many good deals on Gasoline specific oils, I just go with them. I use diesel rated oil in all my small engines though Generators, pumps etc.. I believe it is tougher oil.
Alot of diesel oil was made for mixed fleets and as a one use oil. It's all my Dad used.
15w40 for everything that took oil with no issues.
 
1993 Ford Ranger - 284,000 miles
1995 Chevy K3500 - 271,000 miles
Both still running great, no sludge inside at all.
always, always always on the cheapest 15W-40 available.

What happens if you use "diesel" oil?
Your engines last a half million miles, LOL!
 
It is true that 15W-40 HDEOs are usually very stout oils and can be bought for very cheap if you know where you're looking ( specially if you buy in bulk ).
I am considering switching both my cars to Shell Rimula R4X 15W-40 which is a SL/CI-4 HDEO which i can get for really cheap online, instead of the 20W-50 i am using in both currently.
 
Originally Posted By: RLS
The biggest problem with running diesel oil in cars and pickups is the phosphorus content is to high. It may kill the cats. We had this issue in our fleet when we tried to run 15w-40 in all our vehicles, high cat failures. When we went to running the proper spec. oil in every thing, cat failures when way down.
Just saying.........
I know that most Chevron and most Mobil diesel oils have lower Phosphorus amounts. They also carry the SN rating. A easy way to check is if Ford approved it for their 6.7L, I would not put it in a new car engine.

Just saying........


That is the beauty of living in a state that doesn't check emissions or any other kind of vehicle inspection mandates. Cats fail? Who cares. But that being said, I use a conventional gasoline oil that has comparable phosphorus as many current HD oils in my 2006 Cadillac and it hasn't lost a cat yet.
 
Originally Posted By: TiredTrucker
Originally Posted By: RLS
The biggest problem with running diesel oil in cars and pickups is the phosphorus content is to high. It may kill the cats. We had this issue in our fleet when we tried to run 15w-40 in all our vehicles, high cat failures. When we went to running the proper spec. oil in every thing, cat failures when way down.
Just saying.........
I know that most Chevron and most Mobil diesel oils have lower Phosphorus amounts. They also carry the SN rating. A easy way to check is if Ford approved it for their 6.7L, I would not put it in a new car engine.

Just saying........


That is the beauty of living in a state that doesn't check emissions or any other kind of vehicle inspection mandates. Cats fail? Who cares. But that being said, I use a conventional gasoline oil that has comparable phosphorus as many current HD oils in my 2006 Cadillac and it hasn't lost a cat yet.


Quite often when the cat fails, it completely melts down and turns into a solid lump, completely blocking the exhaust and leaving you stranded. They can also get hot enough the vehicle can catch fire.

Many vehicles will also get reversion in the exhaust and suck the cat material back in through the exhaust valves. Engine does not live long after that.
 
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And the cats on my Caddy haven't failed in 12 years using oil that has a HD level phosphorus. One would think, as your post suggests, that it should be discernible if they did. I understand some's concern in this regard. I just wonder if it is over inflated concern.
 
Originally Posted By: TiredTrucker
And the cats on my Caddy haven't failed in 12 years using oil that has a HD level phosphorus. One would think, as your post suggests, that it should be discernible if they did. I understand some's concern in this regard. I just wonder if it is over inflated concern.


Possibly. Maybe your vehicle does not burn enough oil to make this an issue.
 
Melted cats are from missfires or excessive fuel dumped into the exhaust. Burned oil "kills" the cats...it stops them from reducing emissions but does not "melt" the substrate.
 
Originally Posted By: WyrTwister
Looking at a sale flyer from a local parts store . Noticed the " diesel engine oils " . What would happen if you ran it in a gasoline engine ?

Thanks ,


If your engine does not burn unreasonable amounts of oil, you wouldn't need to think about cat poisoning. "Back in the day" plenty of S-rated oils had big ZPPD comparable and sometimes exceeding diesel oils of today. Also back then, engines tended to burn less oil when new, than they do now. If I took a Corolla into the dealer in 1991 with 1qt/1000 consumption, they'd probably have accepted that as a problem.
 
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Originally Posted By: ArcticDriver
There is a starburst on the container. It will have a CJ-4 or CK-4 rating for diesel.

It will also have a /SM or /SN rating if it is compatible for gasoline engines. (Example: CK-4/SN)

The new CK-4/SN oils promise superior lubrication to the older CJ-4/SM rated oils.

It depends on your specific manufacturer recommendation but typically HDEO (heavy diesel engine oils) are fine for gasoline engines except they are of higher viscosity than gasoline motor oils nowadays which are trending towards 0W-20's for fuel economy.


umm, no, no starburst. The API starburst is reserved for energy conserving oils and none of the dual rated HDEOs are.
Maybe you meant the API donut?
Any dual rated HDEO will have the donut in which the diesel (compression ignition, hence the "C") spec comes first and the spark ignition ("S", get it?) spec comes second.
These are generally high HTHS oils and are well suited to engines calling for a thicker oil.
Old German cars come to mind.
They're intended to be used in fleets having both diesel trucks and heavy equipment as well as some gasser pickups and passenger cars. No need for the fleet operator to stock separate oil for the gassers.
These oils work well in this use and can work well in any spark ignition engine.
Got some T5 in one of my gassers ATM and I haven't owned a diesel in twenty years.
 
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