Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)
 Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

Protect your investment in diesel power and confidently extend drain intervals with our top-grade synthetic diesel oil. AMSOIL Signature Series Max-Duty Synthetic Diesel Oil delivers 6X better wear protection than required by the Detroit Diesel DD13 Scuffing Test for Specification DFS 93K222. Advanced synthetic technology provides excellent viscosity control and outstanding extreme-temperature performance, while minimizing oil consumption. The result: protection that’s boosted to the max.

Package sizes include:

Quart Bottles
Gallon Bottles
2.5-Gallon Bottles
30-Gallon Drum
55-Gallon Drum
275-Gallon Tote

Product Code: DEO • Brand: AMSOIL




MSDS Data Sheet

Product Details Tech Data Reviews & Rating

Product Applications
Use in diesel engines and, where appropriate, gasoline engines requiring any of the following specifications:

Product Application Specs

• API CK-4/SN, CJ-4, CI-4+, CF
• Volvo VDS4.5, VDS4, VDS3
• Mack EOS-4.5, EO-O
• Renault RLD-4, RLD-3
• Cummins CES20086, CES20081
• Caterpillar ECF-2, ECF-3, ECF-1-a
• DDC 93K218, 93K215, 93K214
• DFS 93K222
• ACEA E9, E7
• MB 228.31
• MAN 3575
• MTU Type 2.1, II, I
• JASO DH-2
• Allison TES439
• Deutz DQC III-10LA
• Scania LA-2
• Chrysler MS 10902
• Ford WSS-M2C171-F1

Product Description
Maximum Engine Protection: Wear on rings and cylinder liners leads to increased oil consumption and loss of compression, resulting in reduced horsepower and fuel economy. Independent testing shows AMSOIL Signature Series Max-Duty delivers 6X more wear protection than required by the Detroit Diesel DD13 Scuffing Test for Specification DFS 93K222, delivering the security of providing your diesel the extra protection it deserves.

Viscosity Control
Using top-tier synthetic base oils, AMSOIL Signature Series Max-Duty is naturally resistant to oxidation and the thickening effects of soot contamination. That, along with boosted detergent/dispersant additives, keeps soot particles suspended independently, helping prevent the formation of larger, wear-causing particles. Viscosity increase is minimized and soot-related wear is controlled. Lower volatility also helps Signature Series Max-Duty retain its viscosity after high-temperature service for maximum engine protection and efficiency.

Excels in Extreme Temperatures
AMSOIL Signature Series Max-Duty Synthetic Diesel Oil resists thermal (heat) breakdown better than conventional and competing synthetic diesel oils. Unlike conventional oils, Signature Series contains no wax, staying fluid in sub-zero temperatures for easier starting, improved oil flow and reduced wear. Signature Series 0W-40 (DZF) has a broad viscosity range that offers 4X better cold-cranking ability than a 15W-40, making it excellent for use in both hot-operating engines and cold-weather starting extremes.

diesel oil Scuffing Test

Minimizes Oil Consumption
AMSOIL Signature Series Max-Duty has a low rate of volatility (burn-off), reducing oil consumption during operation and passing less oil vapor into the combustion chamber. It provides up to 76 percent less oil consumption than required by the API CK-4 standard in the Caterpillar-1N oil consumption test.

diesel Oil Consumption

COMPATIBILITY
AMSOIL Signature Series Max-Duty Synthetic Diesel Oil is compatible with other conventional and synthetic engine oils. Mixing AMSOIL diesel oils with other oils, however, will shorten the oil’s life expectancy and reduce the performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed.

Aftermarket oil additives are not recommended for use with AMSOIL synthetic diesel oils.

diesel oil OfficialOil icon

SERVICE LIFE
Diesel Engine Service Life

Heavy-Duty On-/Off-Road: Three times (3X) OEM1 recommendation, not to exceed 60,000 miles/600 hours or one year, whichever comes first.

Turbodiesel Pickup: Two times (2X) OEM1 recommendation, not to exceed 25,000 miles or one year, whichever comes first.

Gasoline Engine Service Life

Two times (2X) OEM1 recommendation, not to exceed 15,000 miles or one year, whichever comes first.

Drain intervals may be extended further with oil analysis.

Refer to your owner’s manual for OEM drain interval recommendations and guidelines for severe and normal service.

Note: Extended drain intervals are not recommended for performance-modified engines, when using biofuels containing more than 10 percent ethanol or 15 percent biodiesel (B15) or for 2007-2009 Caterpillar* C13 and C15 on-highway engines. Extend drain intervals beyond OEM recommendations in these instances only with oil analysis. Note: 2007-2010 Dodge**, Ford** and GM** turbodiesel pickups are also not recommended for extended drain intervals when using DHD.

HEALTH & SAFETY
This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Material Safety Data Sheet (MSDS).

Click here to view the MSDS Data Sheet for AMSOIL DEO.

Keep out of the reach of children. Don't pollute. Return used oil to collection centers.

TYPICAL TECHNICAL PROPERTIES
AMSOIL Signature Series Max-Duty Synthetic Diesel Oil (DEO)
Kinematic Viscosity @ 100°C, cSt (ASTM D-445)15.4
Kinematic Viscosity @ 40°C, cSt (ASTM D-445)94.5
Viscosity Index (ASTM D-2270)173
CCS Viscosity @ -30°C, cP (ASTM D-5293)5555
Pour Point °C (°F) (ASTM D-97)-43 (-45)
NOACK Volatility, % weight loss (g/100g) (ASTM D5800)9.2
Total Base Number (ASTM D2896)10.1
High-Temperature/High-Shear Viscosity, cP (ASTM D5481)4.3
Sulfated Ash Content, wt. % 0.99

Did this product meet your expectations?

(click on a star to rate)
Product Name: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)
Current Rating: 4.87 out of 5 stars
Total Votes: 27 vote(s)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by mistercedric: space

Excellent oil

I have used this oil for many years in my 3500 GMC. A recent trip of 11000 km with the 25000 mile oil filter did not change the color of the oil it was still as if it came out of the container. Excellent starting in cold weather

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Ivan: space

Excellent Stuff!

Great oil at better than dealership prices.
Why wouldnt you?

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by 100 MPH: space

Excellent

I love this oil I rely on it with my lively hood. Great stuff.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Danny Boy: space

Trust

I don't know if my 2013 Ram diesel is protected better by using Amsoil motor oil, but I trust Amsoil research. I believe what Amsoil claims. I can only say this about Amsoil. Only time will tell as the engine ages.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Tamworthsat: space

Great

I would buy this top grade again because I once bought the XL grade and notice a slight drop in mileage.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Mark: space

Nothing else for my diesel truck

I have been using Amzoil in my 2008 Dodge Ram 2500 since the first oil change. I currently have 147,000 miles on it and it doesn't burn a drop of oil, runs smooth and has a ton of power. I believe that using a quality oil with regular oil changes is the key. This stuff is not cheap! Neither is this truck! But to replace it is $68,000. I think the Amzoil is going to give me that quarter million mile mark.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by -King D: space

Too much sauce

Perfect

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Benny: space

I have more faith in this product.

I work my diesel trucks hard. Pull heavy loads 100% of the time. When it's 0° and they start up with quicker oil pressure and less engine clatter, or when it's 95° out and I'm wide open throttle for miles up a long steep grade and my oil temps maintain a steady temperature, I feel more confident my engine will last longer with Amsoil.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by 204man: space

Love it

Cold start 2016 cummins. -23. No problem. Amazing in cold temps.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Frank: space

Only the BEST for Me

I have been using Amsoil since 1979 and I believe in putting the Best Oil in all my Toys . I use it in my cars,garden tractor , lawn mower , whole house generator , power washer , and my 2 Corvettes ,and in my 2013 Kioti CK35 HST Diesel tractor . I guess you could call me an Amsoil Junkie

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Arthur: space

Loyal customer

I just changed the oil in my 2015 with Amsoil for the first time, because the truck came with 2 years of maintenance when bought new, and if you didn't use it your just wasting money.i am a firm believer in Diesel injector clean, I'm on my second Duramax and have never had a fuel related problem. I'll use Amsoil forever.
Thanks for great products.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Clay: space

Works good in cold weather.

08 Duramax 250k miles and still going strong. -30 here in winter, starts up with good oil pressure no waiting on the pressure gauge to pick up cold oil.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by JERRY: space

I change my own oil - have for 30 years. Always Amsoil.

When Amsoil produced a oil meeting Chrysler's requirements (2015 Jeep GC 3.0 Diesel) I jumped on it as I have always had good experience with Amsoil oil.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Marc: space

Best oil for my Cummins,

Only product I use. The BEST!

I use it with AMSOIL FF and bypass filters.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Rob: space

Best 15-40 diesel oil on the market

Excellent product, my 2005 Cummins runs smoother than it ever has. I feel very confident pulling some of the heavy loads that I do, knowing that this oil will stand up to whatever I can put it through.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Mark: space

I'm going to continue using this product.

Very pleased with the purchase. Regens intervals have increased by a significant margin, particularly in the city driving.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Jeff: space

I will stick with Amsoil.

I've been using this in my 2004 Dodge Cummins diesel for 12 years and 120,000 miles and it still runs like it was new.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Douglas: space

5 Star's will always use amsoil

Best oil on the market ! My 2011 Ford F 250 6.7 deisel has 99.687 miles on it and uses no oil between changes !!!

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Dk: space

Winter start

Truck not plugged in -40c slow crank still started. I believe 5-40 made the difference. Good oil

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Novy: space

great

Been using this oil for a while and like it. Cold weather starts a breeze!!!!!!

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by big boy: space

outstanding diesel oil.

could not think of a better oil. longevity, performance, and mileage difference is evident. recommend it for all diesel vehicles. No complaints.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Ihmachine: space

Great product would recommend.

I use amsoil in my 07 diesel truck, I have 7,000 miles on the oil change and still clean according to the lab test! I've used amsoil in different motors and I'm a believer, this oil is spectacular from my personal experience.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by BWW: space

My Ford F250 diesel loves it.

Have been using this product in my 2011 ford diesel since day one. I put on about 14,000 miles a year and change my oil once a year. I have never had to add oil between oil changes. I'm amazed even at change time the oil is still so clear its hard to read the dip stick. Ive been trying to figure out something to put on the dip stick to see the oil easier.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Kevin: space

Easy starting in Canada's North

I have been using AMSOIL Premium 5W-40 Synthetic Diesel Oil for the last five years and I have never had any issues starting when the temperature drops below -30C/-22F.

I switched to AMSOIL after my first winter because I was not happy with the cold weather starting performance of other full-synthetic diesel oils.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Master Bear: space

The Best!!

Amsoil Premium 5W-40 Synthetic Diesel Oil is the best! I have used it on my diesel vehicles for years, and have been quite satisfied with its longevity and performance.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by JP: space

Excellent oil

2011 F250 6.7L. Great oil with great customer service to back it.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Mike: space

Will be buying this for years to come

Excellent performance in my 6.7 power stroke

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)

Reviewed by Ronald Glen: space

Much smoother than RT6

Switched over my 6.0 Powerstroke to Amsoil DEO. After some contemplation, I decided to go with Amsoil for few dollars more than Rotella. I am glad with the decision as the engine has become noticeably smoother. This indicates lower internal friction which will translate into longer engine life. I am already getting 50-70 miles more miles per tank of diesel, which justifies for the slight premium in the price.

Also it appears that I can go longer on the oil. I personally don't believe & was not planning on extended drain intervals as suggested by Amsoil. But with the way things are going, I feel comfortable going 50% more on the oil, which again justifies the higher cost of the oil.

I'll continue with Amsoil DEO, its working out to be lot less expensive than RT6.

Item Reviewed: Signature Series Max-Duty Synthetic CK-4 Diesel Oil 5W-40 (DEO)
Discussion Url

Re: Much smoother than RT6

To overcome extended drain anxiety, consider doing used oil analysis 1000 miles before scheduled oil change.

You can confidently, continue with the oil if the report indicates all the levels to be within spec. Repeat the oil analysis again until the report recommends changing the oil.

This is the most informed and scientific way to establish oil drain intervals. We see conventional oils breaking down below spec before their scheduled interval, indicating accelerated engine wear (even with frequent and regular oil changes). Therefore, the condition of the oil should be the factor that call for an oil change. Replied by Tech Admin
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