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Diesel Oil Selection Guide

Diesel Oil Selection Sioux FallsAMSOIL Diesel Oil Selection Guide

From a “one size fits all” to synthetic oils to match specific needs.

The diesel oil selection here often causes some confusion because they are made for different purposes and the value of one may depend on the use of the truck or the year model. So here I have listed some things about each for you to consider in your decision making process.
As diesel trucks both light duty and commercial OTR are quite the financial investment, always refer to the individual product data bulletin found by using the link to the PDF at the bottom of each product page for more specific information. Please call me at 605-274-2580 with further questions.

Generally the AMSOIL Diesel oils can be categorized in two groups: Longest OEM interval or Premium Extended Interval. These days Sioux Falls drivers can really put on the miles and AMSOIL’s Synthetic Diesel Oils can increase your drain intervals up to three times longer.

AMSOIL Corporate’s #1 Pick
I’ll start with the one one premium product compatible for all diesels – all years – The Premium 100% CJ4. Available in both 5W-40 (DEO) and 15W-40 (DME) this industry leading anti-wear diesel oil lasts up to 3X longer OEM intervals (per notes on package) and offers maximum protection. For more information on this important addition to the industry please visit the specific pages linked above.
Most customers buying AMSOIL are enthusiasts and only buy the premium products thus why this one is becoming the best seller on its merits. Primarily it’s ability to withstand the fuel dilution issues of modern diesel engines equipped with DPF. Dependability and protection when it’s needed.

Older Diesels
For those with older diesels who want our legendary high zinc, long life, chose the Diesel and Marine 15W-40 (AME). It’s great for all 2006 and earlier diesels especially those which may suffer from high soot buildup as this formulation can combat deposits. Be sure to first run a couple bottles of AMSOIL Engine Flush (per sump size) so the unneeded acids are neutralized an purged from the crankcase.  The DME 15W-40 is a CI4+ oil. It’s still my best seller. Guaranteed to last up to 3X longer the OEM interval. Awesome for older cars which require high Zinc or ZDDP. I use it in my 1957 Studebaker.

Best Economy for Older Diesels
For the same 2006 and earlier who want the very best in fuel economy and choose to use a lighter viscosity as recommended by the manufacturer the 5W-30 Heavy Duty Diesel (HDD) 100% Synthetic is the best choice., Product code is (HDD).  I also use this one personally in vintage gas cars which need ha high zinc or ZDDP oil or gasoline engines that have a lot of deposits- this oil’s detergent package is superior to any! But if I had a pre 2007 diesel pick-up this would be my #1 choice. We sell a lot to older Durmax diesels and the Ford 7.3 owners in all climates.

Cost Conscious One Size Fits All (Original Equipment) & for Service Centers
For all diesel owners who are not doing extended intervals but want to use a premium AMSOIL product using the highest quality base-stock, this one is designed to compete on price. Choose the OED 15W-40 Diesel Oil. It meets CJ4 and is also back compatible for all CI4 and earlier specifications. For use in any year diesel new or old. Customers who are going to change oil at the OEM interval but want the  chose between the 15W-40 (OED) or 10W-30 (OEC) you now have a choice. Also popular to those who service diesel vehicles and want one product for all diesel service.

Tractors, Equipment and Fleets
Lastly our original 10W-30/SAE-30 Heavy Duty Diesel which is similar to the AME, High zinc (ZDDP) is generally the choice for work and construction turbo diesels or non-turbo tractors and equipment. Pre 2006 Diesel trucks wanting to use a 10W-30 would select this oil too. Generally the pick for all generators and skid steers as well. CI4 Diesel Specification or earlier.

European Car & Van
Many European diesels call for a diesel/gasoline oil based on specific specifications. For those please see the European Oil Line of products.

Oil Analysis Kits:

In the 12th St. Sioux Falls store we keep in stock the oil analysis kits so you can monitor your oil the most accurate way. Let the analysis company decide and report how much longer you can go between oil changes or filter changes (with our oil bypass filtration kits).  Learn the contamination cycles of your engine and maximize your time and efficiency.

Visit the AMSOIL corporate site to learn more about the most recent tests and trials of our diesel oils. You can also set up your own preferred customer account to buy at cost from. AMSOIL Diesel Protection Shopping Guides anywhere. 


Engine Flush – Most Overlooked AMSOIL Product

Product Overview: AMSOIL Engine Flush

One of my top sellers of course is the AMSOIL Engine Flush but when you take a look at the number of oil changes we sell really only about 15% are adding the flush to their order. In reality at least 75% of all the oil changes that are using AMSOIL for the first time with over 25,000 miles should use it.
Among the many reasons to use a walk-in customer had the following to say:
“My truck  (Ford F-150 non-ecoboost) was using about a quart of oil every 4000 miles or about at 3-months. I used the flush on the last oil change per your recommendation on using it to neutralize acids in order to help the oil’s detergent last longer and low and behold it also stopped from then on using oil!”
AMSOIL Engine Flush – Recommended for any engine with over 25,000 miles (Order FLSH-CN)
Well then this low cost product actually ensures our detergents will last longer by neutralizing the acids which are caused by deposits. It’s designed for all modern seals and gaskets. So it helps you get more out of the AMSOIL motor oils. The flush is also non-solvent based – Non-flammable meaning it’s not harsh on engines and contains nothing different that what is already in our oil – essentially a concentrated form of the detergents and depressants. That also makes it more environmental friendly. The flush helps reduce lifter noise, increases mileage by improving compression. Effectively addresses deposits around piston rings which rob power and cause blow-by. Helps the motor control temperatures. And as we learned – lessons blow-by aiding in better crankcase ventilation.
You want to take care of any deposits early and the volatility of non-synthetics or competitor’s synthetics which are likely to be of the Group III nature can potentially leave deposits in engines which run under severe service. In most applications you only need to use it once but on higher mileage engines which you may not know the history you may find two applications are necessary – meaning one at the time of each subsequent oil change. I can personally attest to that need in my 83 Eagle which was sludged up when I bought it. Slowly using our HDD 5W-30 (high detergent Heavy Duty Diesel & Gasoline Synthetic), flush and our bypass kit (BMK-21), I have improved mileage and oil consumption significantly.
Any car with more than 50,000 it’s a must. Customers do notice a difference. Use approximately one bottle for every 10 quarts of oil.
Amsoil Engine FlushAnd a note on the conditions which will create the need to flush – Sioux Falls winters especially – every time you cut that engine off and the crankcase drops below 60 degrees you are building up moisture in the crankcase. This eventually creates a condition resulting in wear is the motor is not warmed up properly but subsequently deposits as well so we urge you be aware of this and avoid running the engine for less than 10 minutes after the motor is fully warmed on days below 30 degrees. You need to get the moisture out of the crankcase as often as possible.
So if you are not interested in AMSOIL Synthetic Motor oils, still this makes a reason to visit our store. Our flush is unique – it’s not harsh like popular solvent based ones as it contains no flammables. It is mild enough to be used as a transmission flush as well and quite effective. Full instructions are located on the bottle.

The Only Oil Choice for Turbos – Signature Series

Visit us for all your oil needs:
Synthetic Warehouse Sioux Falls
4610 W. 12th St.  (12th & G right next to Wendy’s)

New Challenges for Lubricants

The increased slate of issues lubricants have to meet (or will have to) as technologies to lower emissions are required, place the burden of expertise on to the customer. AMSOIL wants to ensure the customer these issues have been addressed long before the standard reaches the marketplace. Other problems which occur in new vehicles such as design flaws or specific engine wear/sludging issues are also addressed by AMSOIL’s technical staff swiftly. The superiority of their knowledge and resources available can result in an immediate solution giving drivers more time in between these known problems requiring repair or often solving the problem entirely in both engine and transmission.

Turbocharger Issues

The industry trend toward smaller engines that deliver increased power and fuel efficiency has been well documented. The AMSOIL Newsstand contains several articles about the key technologies that enable today’s advanced engines – turbochargers, gasoline direct injection (GDI) and variable valve timing (VVT). These articles have mainly addressed how these technologies affect motor oil.

In short, they’re brutal on oil. It’s one of the reasons more automakers are installing synthetics at the factory.

Fuel dilution can be a problem

To summarize, GDI technology locates the fuel injectors directly in the cylinder (hence the name), as opposed to the manifold. This arrangement allows for greater control over injection, allowing engineers to fine-tune engines for greater efficiency and power. A side-effect of this process, however, is fuel contaminating the oil. As fuel is sprayed into the combustion chamber, it can wash past the rings and down the cylinder walls, into the oil sump. Ford* has seen the issue frequently enough to release a technical service bulletin (14-0040) titled “Fuel Odor From Engine Oil and/or Engine Oil Level Overfull” to address F-150 trucks equipped with the 3.5L Ecoboost* engine. Fuel dilution varies by engine type and driving conditions, with some vehicles showing no issues.

There are two main side-effects of fuel in the oil. First, fuel thins the oil, sometimes reducing the viscosity below the specified grade. If not accounted for in the design of the engine, this can affect wear rates and have an effect on systems that use the oil to function, like VVT.

Second, significant fuel contamination increases the rate of oil degradation. For these reasons, oil analysis labs typically condemn oil samples when the fuel content is greater than 5 percent.

Low-quality oils no match for turbos

Many GDI engines are turbocharged (TGDI). Turbos push more air into the combustion chamber, and tuning for efficiency can improve fuel economy, especially when combined with other technologies, such as direct injection. Operating at up to 150,000 rpm on exhaust gases that can exceed 1,000°F, turbos create extreme conditions that can cause low-quality oils to quickly break down, creating deposits and shortening the life of the oil. By 2020, industry experts predict nearly every new vehicle sold will come equipped with GDI technology, and the vast majority will be turbocharged.

Many motorists – and even more in the future – probably see only the tremendous benefits of improved power and fuel economy from their TGDI vehicles. Most don’t realize the toll modern engines take on motor oil.

Like most vehicle manufacturers, AMSOIL has long recommended different service intervals based on “normal” or “severe” driving conditions. Turbocharged vehicles are automatically included in the severe service category due to the extreme heat they generate. To ensure customers have the information they need to properly maintain their vehicles, a notice will soon be added to the AMSOIL Product Guides at that reminds owners of turbocharged vehicles to follow the severe-service recommendation. That means customers using Signature Series Synthetic Motor Oil in TGDI engines can extend drain intervals up to 15,000 miles/700 hours/12 months, whichever comes first, and should only extend oil changes beyond that with the guidance of oil analysis.

AMSOIL synthetic motor oil delivers superior protection

As proven in numerous tests, AMSOIL synthetic motor oils deliver outstanding protection for these challenging engines. For example, the TEOST Test (see graph) determines an oil’s tendency to form deposits at high temperatures and is a good indicator of turbocharger protection. In the test, Signature Series 5W-30 Synthetic Motor Oil minimized deposits and easily surpassed API SN requirements. In the extreme heat of the Sequence IIIG Test, Signature Series scored 86 percent better for piston deposits than required by API SN, even after doubling the length of the test.

Oil Deposit tests - Brands compared

Here at our Sioux Falls location we get a lot of Subaru WRX and STI owners who know the trouble the run of the mill synthetic causes if it’s not the true PAO base 100% as AMSOIL Signature Series. With AMSOIL Signature or European Series you never have to worry about coking or burnt deposits caused by other so called “fully synthetic” products as long as you follow the severe service oil change interval. AMSOIL is the key to enjoying long life turbocharged performance.

Even in older cars with turbos (Corvair, Chrysler Laser, Mitsubishi 3000GT and so on) can enjoy better performance using our Signature Series.

clogged oil passages on turbocharger unit.

This would never happen with a top quality synthetic motor oil.

Material from turbo oil passages. Volitile non-synthetic oils will do this.

Material extracted from turbo’s oil ports due to inferior motor oil choices.

Turbo inner workings

The above shows how close the oil gets to extreme exhaust temperatures.

AMSOIL - The Only Choice for Turbos

Visit our Sioux Falls location at 4211 South 12th St. Just down the hill from L and across the street form the Hardees stop.

Call us at 800-579-0580

Note – this link opens an awesome Turbo 101 learning page by Honeywell.

Industry Leading 5W-30 Synthetic Motor Oil

This may have been the first blog post I should have written because the best seller of ours is also the one which sets the benchmark for the industry. Although the AMO 10W-40 was AMSOIL’s first product, the 5W-30 is certainly the most popular and of course the one which has had the most scrutiny.

AMSOIL’s Signature Series 5W-30 is one of the only 100% synthetic lubricants widely available on the market. Once you know about it and the finite details of it’s capabilities as a lubricant, problem solver and time saver there’s no turning back!!

Basic benefits include:

  • longer engine life
  • Unparallelled protection under the most extreme conditions (Saved repair costs).
  • Better fuel economy
  • Saved time (up to 25,000 mile intervals or 1-year)
  • Saved money – Less stops for service
  • Warranty Secure
  • Faster Warmups

The main feature of the Signature series line trumps all the benefits in my opinion and that is performance. You can actually tell a difference when running this oil over any of our competitors. The reason is simple.

100_0102Nothing is held back in the additive blend for this and other Signature Series products. This is why it’s the best in the industry. I’ll quote AMSOIL’s Vice President Dean Alexander, “When selecting additives and base stocks we are the only company who avoids making decisions based on cost. If there is a better product or a trend for something better AMSOIL is known in our industry to be the first to get it to the consumer with our legendary blending experience. That is our business, the business of being the best, not turning profits for share holders.”

You can print out the data sheet which follows this link to see the properties.

One particular use I suggest the ASL 5W30 (ASL is the product code to identify this product) is for older cars which you may not know the history of. Assuming the motor was at one point briefly overheated or for various reasons fuel made its way into the crankcase (in modern vehicles which run hotter than prior decades have more fuel dilution issues than ever before), you need to assume there are deposits. Deposits and the sludge which forms deposits become highly acidic when combined with moisture. This results in acids which are 1/3rd of the cause for engine wear. Only a high quality motor oil like AMSOIL’s Signature Series will neutralize this. There are varying quality levels of the additives. AMSOIL only uses the best performing additives and in this case we are talking about the detergent which unlike our competition, will fulfill it’s duty over that long oil change interval.

In that older or not-so-well maintained engine the AMSOIL Signature Series will halt the expansion of more deposits as well as halt the wear that has resulted from. The product will also significantly reduce the stress on components which the competing petroleum based synthetic or standard petroleum oil has caused. Of course our detergent based engine flush is recommended first to further allow our detergents to have more effect once the existing deposits are neutralized.

So if you can really push a new or good high performance engine to unheard of extremes using our motor oils, it’s really the cars & trucks you really depend on which need this. That 85 Chevy Caviler or Geo Metro can see another 100,000 miles just by adjusting your oil!

Great for high mileage engines. Actually all motor oils should be for high mileage engines but just knowing the fact that one manufacturer would make an oil strictly for that, one could assume the others are not and by that you could assume the oil’s detergents are not up to the task.

Another additive selected from a pallet of 20 or more quality levels is the seal sweller. Again, AMSOIL’s selection is based on the benefit to the customer and not the overall cost or profit margin. (No stockholders – AMSOIL is family owned)

To answer one of the most popular questions  – yes, you can use this in any age of motor. AMSOIL is developed so that no compatibility issues occur. The average customer who switched to our gasoline motor oils has about 130,000 miles.

As an AMSOIL dealer we are always excited to hear from our new customers after trying our top tier products. Their impressions serve them as lifelong customers!

Ches Cain