The importance of fluid choice

Does this sound familiar? 

Consumer:  “What oil belongs in my car?”

‘Expert’ response: “Doesn’t make any difference.  Just put the cheapest stuff you can find.”  Or, “I know your car calls for 0W-20 but that’s too thin.  Put straight 40 weight in it.”

If there were only one choice it would be easy

It’s a bad thing when the “expert” is Uncle Joe, the shade tree genius, it’s close to criminal when the “expert” is one of us in the industry.  Once upon a time, you could get away with putting just about any fluid in a vehicle.  Today, put the wrong oil in an engine and you might cut its life down to a few weeks. 

That goes for all of the other fluids in a vehicle.  Put the wrong oil in a CVT transaxle and you won’t get out of the parking lot.  The wrong coolant or coolant blend and the heat exchangers might begin leaking within hours. 

Using the incorrect brake fluid could result in an accident and legal liability.  Wrong transmission fluid can lead to poor shifting or worse regardless whether it’s an automatic or manual box. Power steering fluid can change the life of the steering box. It can also effect the braking system on vehicles with hydro-boost.

Using the wrong oil in an A/C system, especially the high-voltage units in a hybrid, and you could end up replacing every A/C component on the car to correct the mistake.

Things have changed – a lot! 

Unfortunately, this is a topic that gets people’s dander up, so let me start with one statement that is as close to an absolutely true, inarguable statement, as we can in this business, and then we can move on:

There is only one way to ensure that you are using the correct fluids for your customers.  Use only fluids that are recommended and approved by the manufacturer. 

Motorcraft Premium Gold coolant

What is arguable is whether or not there are better products than the factory recommended and approved.  Can you find and use fluids that are better than OE?  The answer is a definitive, yes, no and maybe.  Though I’m still not sure one can have a rational discussion about DexCool, the question is answered by knowing what the manufacturer requires and then doing some real Dick Tracy research into products.

We all have seen the statement by an OE saying that not using a certain fluid might result in the warranty being denied. A disclaimer to this statement: Under the Magnuson-Moss Warranty Act, a manufacturer cannot force you to buy or use a specific name-brand product to maintain a warranty.  What they can require is that fluids and components used must meet their standards or they might be able to deny a warranty claim. 

Each manufacturer will have specific specifications for fluids. If you want to use something else, your task is to determine what makes an oil meet dexos1™ specifications, for example, and then see if you can find one that has equal to or better than those specifications, if it is not GM approved. 

Keep in mind that a manufacturer of fluids might advertise that its fluids exceed manufacturer’s specifications.  Laws related to what and how they can advertise are somewhat loose. Which specifications do they exceed?

Also complicating the process is when a manufacturer revises specifications of product and then does not grandfather them to previous models.  Here’s an example. When I worked for Ford, I was in new model training for the 6.0l PowerStroke.  Engineers from Navistar did part of the training.  As they discussed the coolant requirements for this engine, they talked about the benefit of using the new MotorCraft Premium Gold coolant.  It had all of the additives for a diesel already in it.  It was the factory fill, and both Navistar and Ford recommended and approved it.

I asked them if we could recommend that technicians use this new coolant in the 7.3l engines.  Their response was, “No”.  When I pressed them to explain why, one of them simply stated that they had not tested that coolant on those engines and so they did not know if the chemical mix in that coolant was compatible with the materials in the 7.3l engines.

In reality would MotorCraft Premium Gold work in those engines?  Yes, it probably does, however the real question is: for how long would it work?  Does Ford recommend it yet?  No, it does not.

The Castrol Product in the center I can use without worry in a GM vehicle.  It is dexos approved.

I know many of you will want to email me and tell me that you have successfully used this or that, and I believe you.  I’m here to tell you that it only takes a small amount of time on the web to find out that using fluids other than specified sooner or later will have an effect.  I can give story after story from just my experience with Ford of technicians who related the tales of woe from people who used the wrong fluids in their vehicles.  Oil filters blown off at startup due to wrong weight, variable cam timing mechanisms unable to move due to sludge. Was that sludge from lack of maintenance or non-approved oil? 

Let me illustrate clearly the value of using the correct fluid in your vehicle and in your customer’s vehicles. In this case oil.

I owned a 2002 Ford Focus and put 200,000 miles on it before passing it on to my sister-in-law. I work 66 miles from my home, so I am filling up every other day and can keep track of fuel economy easily.  I had an oil change at a local Ford Dealer.  At my next fill-up two days later suddenly my fuel economy was down from 30 to 26 mpg.  Again two days after that, 26 mpg.  I got my IDS out and looked at numbers, no codes, fuel trims normal, MAF frequency were it belonged. 

The problem?  They put the wrong oil in my car.  I don’t know what it was, but as soon as I went to Motorcraft Semi-Synthetic 5W-20 (recommended and approved) my fuel economy went back to 30 mpg.

I recently was talking with someone and told them this story and they related their experience.  This person had purchased a Honda with around 200,000 on it.  It got very poor fuel economy.  Talking with the previous owner that person had used a much thicker oil than recommended.  The new owner has been using the correct grade of oil and is now getting five to six miles per gallon better than when he bought it. Yes the other “worked,” but at what real cost?

Wait a minute, why is there pink coolant in this 2012 Ford Focus?

Why the need for this concern today as opposed to yesterday?  Take a look at engine specifications from engines in the 1960s, ’70s and ’80s and then look at a modern modular engine.  Typical engine tolerances today are in the .01-.02mm range.  Now if those numbers don’t mean much to you because you learned English numbers let’s convert: .02mm rounded up is .0008 inch.  That is not a typo.  Two hundredths of a millimeter is less than one thousandth of an inch.

Trying push a 40 weight oil through a space that was engineered for 20 weight might simply reduce fuel economy, it might cause engine damage.  It might not exhibit any concerns for miles, it might not get out of your parking lot. 

At this point some of you are still saying that, “OEs buy oil in bulk at the cheapest price and lowest quality they can find to make it work.”  When I was still working for Ford, I had access to some of the internal engineering sites on the Ford Intranet.  I have two documents, which I cannot share copies of, that discuss this point. 

One was the spec sheet for bid for oil companies to provide oil for factory fill. At the time of the document’s creation Ford was anticipating the new ILSAC GF3 spec.  They created specs for the 5W-20 oil that matched the anticipated GF3, in some case making the match the minimum requirement.  An oil company was free to bid at the minimum requirements or exceed those requirements if they wanted to provide the factory fill.

In reality this same process goes on for all fluids in OE vehicles.

Ford has clearly shown you what weight of oil to use, no mystery here.

So the next question to answer is: if you want to use a different brand how do you decide what will or won’t work?  With oil it would be wonderfully simple if all you had to do was go to the API (American Petroleum Institute) service classification list and choose your substitute oil by picking the latest classification and then the appropriate weight. Now that’s a good place to start but there are still cautions to concern yourself with as I described above.

You also need to be concerned with ILSAC (International Lubricant Standardization and Approval Committee) standards and ACEA which is the European Automobile Manufacturers’ Association.  An oil may meet API Service Classification SN but may not meet ILSAC G5. Likewise an oil may meet an API and ILSAC classification but not ACEA.  ACEA classifications are letters with numbers such as A1, A2, etc.    ACEA has letter designations for different engines, going A to E.

What you will need to do is to search out the specification sheet for the recommended approved fluid that you wish to change.  You may need to pull the Material Safety Data Sheets (MSDS) sheets as well.  You then compare what the fluid is to the fluid you want to use in its place.  As you do this you will find out some interesting things.  For example: Looking at a spec sheet for a couple of Castrol Edge products.

Castrol Edge with Syntech 0w-30 is substantially thicker at 100C than their 5w-30.  In fact the 0w-30 is almost a 0w-40 oil.  Castrol Edge with Titanium is a “thick” 20 and “thin” 30. Look at the chart below for viscosity for the different weight classifications.

You cannot simply use just the viscosity rating to make your choice.  That is not saying that either of these is a “bad” oil.  Knowing whether the oil you want to use is thick or thin is simply one of the things you need to know before you make a change.

Coolant has the same issues.  There are basically three types in common use today.  In and of themselves they are not really compatible.  Therefore is there such a thing as a universal coolant?  I was convinced that there wasn’t for many years.  In 2012 I was one of a number of trainers who was invited to Prestone’s headquarters and given a tour, training, and a chance ask the questions of the chemists who make their products. 

After the training I have come to the conclusion that yes there are coolants that are top-off compatible with OE coolant.  How can that be?  I have to admit that having a chemist who holds multiple patents from different countries tell me that a product can be created that is chemically compatible and then show how they test the product to confirm compatibility is pretty compelling.  You still need to check the specs.

Like our discussion of oil above, coolant has standards set by the OE these can be compared to the aftermarket product and a decision can be made. Also as our discussion above suggests correct maintenance, inspection by owners and technicians is a critical factor in making sure that coolant stays coolant and not a reactive sludge that eats water pumps and heater cores for lunch.

In my research and observation the main cause of early cooling system failure is incorrect servicing.  Whether it is the tech doing a service who doesn’t check the level and acidity to trying to change out coolant without using the tools needed to get 100% of the old out. To the owner dumping something in themselves. Proper maintenance is the key to long life of even long life coolants.

Perhaps the number one cause of cooling system damage over time comes from a system that is not full and has air in it.  CO2 – O2 will react with the coolant and will begin to create an ooze that may result in electrolysis, cavitation, or blockage… a broken vehicle that may need hundreds to thousands of dollars of repairs.

Brake Fluid, Power Steering Fluid, Transmission Fluid, Rear Axle Fluid, every single one of these fluids has an OE specification and every single one, like oil and coolant have aftermarket products that claim to be better than what came from the factory.  Some of them are and some of them aren’t.

This oil meets ILSAC G5, ACEA A1/B1, and API SN.  It still may not meet the requirements of the vehicle you’re working on.  

Pretty much all of today’s vehicles are easily capable of two hundred thousand miles of mostly trouble free operation.  As I said above the “easiest” way to help your customers is to use fluids that are approved by the OEM.  Finding fluids that are better than OE requirements requires you to put in some serious research and to continue to stay up on changes in fluid specifications and OE recommendations. Even if you choose to use OE approved you still have work to do to keep current.

At this point in the this piece I could start laying out how to read the API Starburst, discuss the ILSAC and ACEA specs in some sort of a graph, but the teacher in me won’t let me.  Oil requirements change too fast and too often.  You need to learn how to do it for yourself. I have laid out a case for your need to be:

ü  Vigilant in keeping up with changes in requirements by the OEMs

ü  Move beyond just looking at listed viscosity ratings

ü  Move beyond advertising claims

How do you go about trying to find non-approved fluids that are better than or even simply meet OE requirements?

You will need to familiarize yourself with the organizations that certify fluids. You will need to learn enough about terms like viscosity, High Temperature/High Shear Viscosity, Pour Point, centiStokes, and other specifications for the fluids you want to use.

1.     Throw out your old attitudes about thicker vs thinner oil, importance of color of coolant, (it’s not a valid check) etc.

2.     Get over the attitude that “it worked for me in the past, it will in the future”

3.     Find the OE’s requirements for the fluid

4.     Look for TSBs related to changes in recommended fluid applications

5.     Find the specifications for the fluid you are considering

6.     Compare the specifications and make your determination

That’s the easy part, after that you will need to:

1.     educate your employees to properly inspect and service vehicles

2.     educate your customers of the needs of today’s vehicles including

a.     interval inspections

b.     unique fluid requirements

There are a number of places on the internet to help you become acquainted with and perform your research.  One of these is Bob the Oil Guy: http://www.bobistheoilguy.com.  Another good place is to become and sponsoring member of iATN : www.iatn.net and search the forum archives.  Of course there are also articles that have been in MotorAge over the years that you can look up as well. Again let me caution you to keep in mind when articles were written.  This stuff changes all the time, what was true three years ago is likely outdated and wrong today.

It is a challenge and just another example of why being in the automotive repair industry is not for the faint of heart.  Making sure your customers get the best products in their vehicles requires you to be a detective, student, educator, and diplomat.  

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