As General Motors Corp.s vehicle sales climb to record volume worldwide, the behemoth automaker reminded automatic transmission fluid suppliers that its trademarked Dexron-VI global specification is more important than ever, and warned that there is no such thing as an ATF that meets universal specifications.
Speaking at the Uniti Mineral Oil Technology Congress in Stuttgart, Germany, on April 15, GM senior lubricant engineer Khaled Zreik noted that 2014 was a record year for the Detroit-headquartered company, having sold 9.9 million vehicles throughout more than 120 countries.
In China, the automakers largest country market, sales spiked 12 percent from the year before to surpass 3.5 million units. The U.S. market followed at 2.9 million units sold – a 5 percent increase from 2013.
Dexron-VI is the worlds most prominent ATF brand, not just in number of licensees but in yearly sales volume as well, according to Zreik. Based on automatic transmission production figures, he added, almost 11 million gallons of Dexron-VI approved fluids are used around the globe. Of that volume, 47 percent is sold in the United States, 26 percent in Mexico, and 21 percent in China.
He emphasized the importance of following original equipment manufacturers guidelines for service-fill ATF, and warned that end users should be wary of the myriad ATFs in the market that claim to meet universal specifications – such as both GMs Dexron-VI and Fords Mercon V – as each is different, and such universality is impossible.
Furthermore, Zreik stressed that aftermarket additives cannot convert or uptreat one fluid to another. We always see these kinds of claims, and have tested way too many such products. The results always show that the claims are hilarious.
To compete for ATF factory-fill contracts at GMs 400-plus manufacturing facilities, Zreik reminded suppliers that products must gain its Dexron-VI stamp of approval.
The Dexron brand name dates to 1967, and took over from the Type A fluids that were used in GMs earliest automatic transmissions in the 1940s. Dexrons drain interval was just 25,000 miles – no improvement over the Type A recommendation – but it jumped to more than double that with the introduction of Dexron-II in the 1980s, and again to 100,000 miles when the Dexron-IIE specification was issued in 1989.
More upgrades followed, as GM imposed stricter factory-fill requirements over the next decades. By 2005, the current Dexron-VI specification was ready to launch. It requires a minimum drain interval of 150,000 miles for cars and light-duty trucks driven in normal service, which is 50,000 more than GMs previous Dexron-III(H) specification. For vehicles driven in severe use, the service change interval is 50,000 miles.
Longevity was not the only upgrade Dexron-VI offered, Zreik emphasized. Dexron-VI fluids improved clutch friction stability, clutch durability and fluid oxidation parameters by 100 percent or more beyond its immediate predecessor, he noted. The upgrade also required foam-and-aeration and shear stability measurements that are 150 percent and 200 percent better, respectively. Oil film thickness rose 20 percent, to deliver significantly better wear protection, Zreik said.
Dexron-VI was also designed to align with GMs corporate goals, such as having one common ATF that could fill and service its cars and light trucks worldwide. Fill for life was another stated objective, to assure lower cost of ownership and improved customer satisfaction.
Only licensed products can display the Dexron-VI trademark, and suppliers can earn a license in three ways:
1) As an original formulator with a new blend of base oil, additives and thickeners. This requires the candidate ATF to pass a comprehensive set of tests at one of two approved independent labs, which cost around $110,000. Twelve companies have this level of approval, although some have multiple formulations under license.
2) As a re-blender, which requires permission from the original license holder to blend its formula, with no deviation, plus a set of key tests that costs around $40,000.
3) As a re-brander, which only requires permission from either an original license holder or re-blend license holder to resell its licensed blends under ones own brand.
Zreik noted that all candidate fluids for original or re-blend Dexron-VI licensing must be submitted for testing at one of two independent laboratories – Southwest Research Institute or Intertek, which are both based in San Antonio, Texas. GMs own ATF Committee reviews and approves all submissions, and makes the approval decision.
General Motors earns a royalty on every gallon of Dexron-licensed product sold, but it does not charge anything directly; instead, the cost is built in to the additive package needed to blend the product. All four of the leading global additive manufacturers – Afton Chemical, Chevron Oronite, Infineum and Lubrizol – offer Dexron additive packages.
There has been a great increase in licensing of Dexron-VI, Zreik told the Stuttgart gathering, pointing out that GM issued only about 20 licenses in 2006. That has grown to almost 200 individual licenses now. Of the various formulations carrying Dexron-VI approval, Zreik noted that each type of base stock is represented – from API Group I, II and III, to polyalphaolefin based products and even those derived from gas-to-liquids technology.
Recognizing a good thing, GM also has hitched the Dexron trademark to a broader family of factory-fill and aftermarket drivetrain fluids. The current portfolio of Dexron-approved products extends to high-performance ATFs, dual-clutch transmission fluids, gear oils, hydraulic fluids – even automatic transmission seal conditioners.
Meanwhile, more stringent transmission designs have prompted GM to develop an ATF with lower viscosity to boost fuel economy, greater wear control, antifoam performance and oxidative stability. GM calls this latest specification Dexron HP (for high performance), and despite being lighter in weight, it is intended to go beyond 200,000 miles in the most advanced powertrains. So far, only four companies have obtained licenses to supply Dexron HP: Chevron, Shell, SK Lubricants and Valvoline. This fluid is required for its new Hydra-Matic 8L90 eight-speed automatic, an advanced eight-speed, rear- and all-wheel-drive transmission thats an option on GMs full-size trucks and SUVs and the Chevrolet Corvette.
Compared to its six-speed automatics, the Hydra-Matic 8L90 is said to contribute up to 5 percent more efficiency. It does this by using smaller steps between gears, keeping the engine always within the sweet spot of the rpm band. Built at GMs Toledo, Ohio, plant, it occupies the same space as prevous six-speed models (the 6L80 and 6L90), but carries just 10.5 liters of fluid; those 6-speeds needed 13 liters.
Even greater hardware challenges lie ahead, such as a 10-speed automatic transmission, and Zreik expects to see no lessening of the emphasis on creating fluids that can boost fuel economy – probably by driving down the viscosity. Such an ultra-low viscosity product would demand lower viscosity base oils, and may also require new pump architectures. As a consequence of lower viscosities, better chemistry is needed to provide hardware protection, he added.
Another key element of ATF formulations, the antifoam package, will also have to be scrutinized. Lower viscosity will test an antifoam system, Zreik cautioned, and older antifoam additive packages will not be good enough.
For more information on the Dexron-VI licensing program, go to www.gmpowertrain.com/VehicleEngines/dexron-vi.aspx.