Refining your engine oil selection: Oil is oil, right? Wrong!

Aug. 15, 2012

About the author: Weber is president of Virginia-based Write Stuff. He is an award-winning freelance automotive and technical writer and photographer with over two decades of journalism experience. He is an ASE-certified Master Automobile Technician, and has worked on automobiles, trucks and small engines. He is a member of the Society of Automotive Engineers (SAE) and numerous other automotive trade associations. He has worked as an auto service technician, a shop manager and a regional manager for an automotive service franchise operation.

Carmakers are getting picky. Once upon a time there was one universal type of antifreeze. Once upon a time, there were two types of automatic transmission fluid. Once upon a time, there were just a few common grades of motor oil. Times have changed.

Think using the wrong oil in today’s engines is “not a big deal?” Think again! The incorrect engine oil selection can not only lead to premature wear and tear of internal engine components, but it can also cause major drivability problems.

Of course, we all know that using the wrong oil will not result in immediate catastrophic failure, but over time it can take its toll.

AutoInc, the journal of the Automotive Service Association, reported that:

Sometimes the wrong motor oil gets used in a vehicle, and despite the imaginative illustration that pictures an engine immediately seizing up, the likelihood of that is small. But, even though an engine doesn’t completely seize up from using the wrong motor oil doesn’t mean damage doesn’t occur. “If a Corvette was given starburst oil because someone didn’t read to know it needed a special oil, there wouldn’t be immediate failure,” said [Mark Ferner, lead product engineer, Pennzoil Research and Development]. “But over time, problems would likely develop.”

According to Ferner, small mistakes may lead to big damage. “The right oil will have the right balance of base oil and additives for a given engine. If an oil lacks the right components or the right balance, bad things may happen. Depending on which additive is missing, you can have metal-on-metal contact in the valve train. A motor oil lacking certain antioxidants could see heat damage since local hot spots in the engine spike to 400-600 degrees F. Over time this buildup of varnish can keep parts from moving properly.”

But just as automakers have been moving toward specific coolants and automatic transmission fluids, they are starting to demand specific oils for their engines.

European automakers started steering away form the universal, one-size-fits-all concept in the 1990s.

For example, BMW, with the introduction of the 1999 3-Series (which the company calls its E46 series), introduced extended oil changes of up to 15,000 miles (or once a year). At the same time, the company introduced BMW High Performance Synthetic Oil SAE 5W-30.

Castrol was the first to produce a compatible oil for the American market.

According to Liqui Moly, “Oil must now be capable of much more than just lubricating and cooling: It must function even at elevated temperatures and pressures; it must clean the engine from combustion residue, grit, acids, water and fuel particles; it must protect the engine from corrosion and keep its density. Modern engine oils are high-tech liquids designed specifically for use in certain car models, practically tailor-made replacement parts.” As a similar example, not every engine can use the same spark plug.

What happened to Audi about 10 years ago set the stage. Audi and Volkswagen 1.8L turbo engines suffered from an internal build up of sludge. The oil almost turned tar-like causing severe engine damage. The carmaker narrowed the problem to incompatible engine oils that did not meet its specifications.

As a result of a class action lawsuit, the carmakers extended the warranty to 10 years or 120,000 miles.

These were not inferior oils or off-brands, but well known brands meeting API and SAE specifications. Volkswagen and Audi have a special oil requirement and the extended warranty was only valid if car owners used the proper oil meeting the VW502.00 spec. And it must be synthetic oil.

Recently, General Motors has established a new engine oil standard known as dexos1 (yes, with a lower case “d”).

According to the GM dexos information center, the company manufactures cars and trucks in 34 countries and sells them in over 140 countries. These vehicles contain an array of more than 20 different engine sizes. To function well and to last a long time, these increasingly high-performance engines need consistently high-quality oil, and that quality and uniformity needs to be available anywhere in the world.

GM dexos is a proprietary, global engine oil specification designed to meet the requirements of GM vehicles worldwide.

According to the dexos information center, the dexos specification “...has gone through an extensive developmental and testing process. It requires a number of proprietary tests that are not included in current industry standards and sets performance criteria at a level that exceeds many current standards. The result is a high performance fluid providing significant wear protection, improved piston cleanliness, a reduction in volatility and oil consumption, enhanced aeration control for improved fuel efficiency, and better oxidation properties.” The name dexos is an exclusive trademark of General Motors. Only those oils displaying the dexos trademark and icon on the front label have been certified and licensed by GM as meeting the demanding performance requirements and stringent quality standards of the dexos specification. The license holder is required to display its number on the product package.

GM claims that “...using substandard oil can affect engine performance and, in the worst case scenario, may damage or harm the engine. Unlicensed products have not gone through GM’s rigorous testing process, are not monitored for quality, and are not approved or recommended for use in GM vehicles. Unlicensed product quality and suitability for GM vehicles cannot be guaranteed and, therefore, use of unlicensed products may result in lower levels of performance and could cause engine damage that may not be covered under warranty.”


Many oil marketers now offer licensed dexos and can be identified by the dexos icon and license number on the bottle.

For a list of licensed dexos products, go to

GM recommends dexos1 for all its gasoline vehicles and dexos2 for light-duty diesels. The new dexos oil is backward-compatible and can be used in older vehicles. It is specified in the owner’s manual for all 2011 and later model years, with the exception of Europe where dexos is specified starting in model year 2010. GM claims that dexos reduces piston deposits by 28% and boosts fuel economy slightly (0.3%) over GF-4 oils.

Since dexos is a synthetic, the higher price may shock car owners when the have their oil changed and get a bill that is close to $100.

GM is careful to state that, “Using engine oils other than authentic licensed dexos™ products could result in reduced engine performance.” Note that the company does not say that engine damage will occur, only that performance may suffer and that using the poor quality oil could void the warranty. That may be difficult to prove without laboratory analysis. By law, if a company says that you must use a specific oil to keep the warranty intact, it must be supplied free to the customer under the Magnuson-Moss Warranty Act.

There is some concern that the move toward auto manufacturer-specific motor oils is an attempt to force car owners back to the dealership for all service including routine oil changes.

“It seems to me that the carmakers are trying to capture the aftermarket business and to put the fast lube franchises out of business,” said Paul Fiore, director of government affairs for the Automotive Aftermarket Industries Association (AAIA).

In a 2009 SAE paper entitled “Gasoline Engine Oil Specifications Past, Present and Global, written by Eric R. Johnson, et. al. from GM, it stated: “...because of the increasing number of individual OEM specifications, engine oil changes will move back to the auto dealerships. This is consistent with the European model of service at dealerships using genuine engine oil as opposed to the North American model of service at quick-change facilities using ‘conventional’ engine oil. The reason that this could happen in North America would be the inability of quick-change facilities to competitively stock the OEM-specified oils. Quick-change facilities depend on their purchasing power of a single bulk brand (or specification such as GF-4) to offer oil changes at a competitive price. This European style of service is being reinforced by the increasing number of OEM’s with 10-20% light vehicle market-share. Since there is not a dominant share held by any one OEM, it could be that only OEM car dealerships will be able to buy their specified oil in cheaper, bulk quantities.”

Interestingly, some well-known brands of oil don’t show up on the list, including Amsoil, Royal Purple and Valvoline.

A spokesman for Valvoline’s fluid tech department said that the company does not offer a dexos-licensed product due to the high royalties demanded by GM. “We would have to pay royalties on every gallon of oil we sell whether it goes into a General Motors car or not,” he said, adding that Valvoline Durablend 5W-30 and SynPower 5W-30 are ILSAC GL-5 oils that are fully compatible (see sidebar on next page).

Royal Purple is pretty much a niche market lubricant, as is Amsoil. Meeting the new specification is not as much of a problem as being able (or willing) to afford the licensing fee.

Some motor oil makers and marketers choose not to.

“Our oil already meets or exceeds the dexos spec,” said Chris Barker, technical services manager for Royal Purple.

Perhaps someday, the universal motor oil will be seen as an old, quaint fairy tale.

Auto warranties, routine maintenance and repairs

A question that many independent shop owners, and even some dealers, regularly hear is: “Do I have to take my car to the dealer and must I only use genuine, original equipment parts? Must I use only the approved oil?” Well, the Federal Trade Commission (FTC) has their answers.

Anyone who owns a vehicle knows (or should know) how important it is to keep up with routine maintenance and repairs. But can a dealer refuse to honor the warranty that came with the new car if someone else performs the routine maintenance or repairs?

The Federal Trade Commission, the nation’s consumer protection agency, says no. In fact, it’s illegal for a dealer to deny warranty coverage simply because the customer had routine maintenance or repairs performed by someone else. Routine maintenance often includes oil changes, tire rotations, belt replacement, fluid checks and flushes, new brake pads, and inspections. Maintenance schedules vary by vehicle make, model and year; the best source of information about routine scheduled maintenance is the owner’s manual.

“Do I have to use the dealer for repairs and maintenance to keep my warranty in effect?”

Tell them no. An independent repair shop can perform routine maintenance and repairs on the vehicle.

In fact, the Magnuson-Moss Warranty Act, which is enforced by the FTC, makes it illegal for manufacturers or dealers to claim that the warranty is void or to deny coverage under the warranty simply because someone other than the dealer did the work. With that said, there may be certain situations where a repair may not be covered. For example, if one of your technicians replaced a belt improperly and the engine is damaged as a result, the manufacturer or dealer may deny responsibility for repairing the engine under the warranty. However, according to the FTC, the manufacturer or dealer must be able to demonstrate that it was the improper belt replacement — rather than some other defect — that caused the engine damage. The warranty would still be in effect for other parts of the vehicle.

“Will using ‘aftermarket’ or recycled parts void the warranty?”

No. Reassure them that simply using an aftermarket or recycled part does not void the warranty. The Magnuson-Moss Warranty Act makes it illegal for companies to void the warranty or deny coverage under the warranty simply because an aftermarket or recycled part was used. Still, if it turns out that the aftermarket or recycled part was itself defective or wasn’t installed correctly, and it causes damage to another part that is covered under the warranty, the manufacturer or dealer has the right to deny coverage for that part and charge the vehicle owner for any repairs. The FTC says the manufacturer or dealer must show that the aftermarket or recycled part caused the need for repairs before denying warranty coverage.

Tips to avoid warranty issues: Here’s how your customers can get the most out of their vehicle’s warranty:

• Make sure they read the warranty. Often bundled with the owner’s manual, the warranty gives a general description and specific details about claims coverage. If the owner’s manual has been misplaced, the information may be obtained online. Tell them to check the “Owners” section of the manufacturer’s website.

• Be aware of the warranty period. If their vehicle is having problems that are covered under the warranty, they need to get them checked out before the warranty expires.

• Bring in their vehicle at regular intervals. This is a good idea in any case. But for the sake of keeping the warranty intact, they need to follow the manufacturer’s recommended service schedule (in the owner’s manual).

• Vehicle owners should keep all service records and receipts, regardless of who performs the service. This includes oil changes, tire rotations, belt replacement, new brake pads and inspections. If the owner creates a file to keep track of repairs, it will come in handy if they need to take advantage of the warranty. If the owner ever has a warranty claim and it appears that they did not maintain the vehicle, the claim could be denied.   ●


Meeting the needs of European vehicles: Modern synthetics meet carmakers’ specs

European carmakers have their own oil specifications. To avoid problems, you should use only an oil meeting that carmaker’s specs. You may not need not stock a plethora of products if you chose products that meet the various requirements. Many modern synthetics from major oil companies meet those carmakers’ specs, but the pressure is on you to make sure the one you use meets what is stipulated in the owner’s manual.

Carmaker          Specification

Audi/Volkswagen          502.00, 505.00, 505,01

BMW      LL-04

Mercedes-Benz        229.51

Porsche            Porsche’s approval

(Source: CRP Automotive Industries – Pentosin Oil)

Dexos-equivalent oils from Valvoline

The following Valvoline products will reportedly meet all requirements of the dexos specification and therefore in GM’s terminology will be dexos-equivalent oils:

Product            Grade   dexos™ spec   Other specifications

SynPower         5W-30   dexos1      ILSAC GF-5, API SN/Resource Conserving, ACEA A5

SynPower         5W-30   dexos1      ILSAC GF-5, API SN/Resource Conserving, ACEA A1

DuraBlend         5W-30   dexos1      ILSAC GF-5, API SN/Resource Conserving, ACEA A1

NextGen DuraBlend       5W-30   dexos1      ILSAC GF-5, API SN/Resource Conserving, ACEA A1

SynPower DuraBlend       5W-30          dexos2      API SN/CF, ACEA A3/B4-04, ACEA C3-08, MB 229.51, BMW LL-04, VW 502.00/505.00/505.01