Automatic transmission fluid

The most common VI improvers are methacrylate polymers and copolymers, acrylate polymers (see Acrylic ester polymers), olefin polymers and copolymers, and styrene—butadiene copolymers. The degree of VI improvement from these materials is a function of the molecular weight distribution of the polymer. VI improvers are used in engine oils, automatic transmission fluids, multipurpose tractor fluids, hydrautic fluids, and gear lubricants. Their use permits the formulation of products that provide satisfactory lubrication over a much wider temperature range than is possible using mineral oils alone. 

Eig. 12. Effect of frictioa modifier ia automatic transmission fluid (21). 

No information concerning the specific production volumes of mineral oil hydraulic fluids was found in the available literature. The National Petroleum Refiners Association (NPRA 1992) reported that 192 million gallons of automatic transmission fluids, universal tractor hydraulic/transmission fluids, energy/ shock absorber and power steering fluids, and other automotive hydraulic fluids were sold in 1991. Virtually all of these fluids are mineral oil hydraulic fluids (Chrisope and Landry 1993 Papay 1989, 1991 Wills 1980). This volume is lower than sales volumes for 1990 (216 million gallons), 1989 (221 million... 

Mineral Oil Hydraulic Fluids. No information identifying the major components of mineral oil or water-in-oil hydraulic fluids was located in the available literature, nor was any information located that described how the emulsifiers and other components in water-in-oil emulsion hydraulic fluids alter the environmental properties of the mineral oils contained in them. The carbon number range present in mineral oil hydraulic fluids probably is from C15 to C50 (IARC 1984 Shubkin 1993 Wills 1980). If automatic transmission fluids are typical of the mineral oil content in a hydraulic fluid, then mineral oil hydraulic fluids contain -90% mineral oil (Abdul et al. 1990 Papay 1989,1991). Therefore, the transport and partitioning of these hydrocarbons will largely account for the environmental behavior of mineral oil hydraulic fluids. Typical transport and partitioning information for hydrocarbons in this range is presented below this information is indicative of the transport and partitioning of mineral oils present in hydraulic fluids. 

Abdul et al. (1990) reported that upper layers of soil were saturated with automatic transmission fluid (ATF) after a storage tank leaked 208,000 gallons onto the surrounding soil. Lower soil layers contained less ATF volumetric ATF concentrations ranged from <10% to 40% at 80-0 cm above the ATF table. 

Abdul AS, Gibson TL, Kia SF. 1990. Contamination of soil and groundwater by automatic transmission fluid Site description and problem assessment. J Hydrol 121 133-153. 

Chrisope DR, Landry JF. 1993. Automatic transmission fluid. In Shubkin RL, ed. Synthetic Lubricants and High Performance Functional Fluids. New York Marcel Dekker, Inc., 351-364. 

Papay AG. 1989. Automatic-transmission fluids Dexron II and beyond. Lubrication Engineering 45 121-128. 

PapayAG. 1991. Formulating automatic-transmission fluids. Lubrication Engineering 47 271-275. 

Perrot LJ, Palmer H. 1992. Fatal hydrocarbon lipoid pneumonia and pneumonitis secondary to automatic transmission fluid ingestion. J Forensic Sci 37 1422-1427. 

Dye. A dye is added to the engine coolant to differentiate it from other functional fluids (such as automatic transmission fluid, brake fluid, etc.) and to signal its presence in the cooling system. The dye should remain stable during the period of use and should not affect the appearance of paint finishes in case of accidental spillage of coolant. 

Dexron II (General Motors trademark specification for automatic transmission fluid, ATF), Dexron-II issued 1993 Dexron-III issued 1998. Dexron-IV issued 2000. 

Ford Motor Company trademark ATF specification. Automatic transmission fluid key test requirements. 

Other interesting products that can be obtained from waste plastics using combined thermal and catalytic processes are alkylaromatic compounds, which possess industrial applications as automatic transmission fluids (ATF), detergents (linear alkyl benzenes, LAB), and improvers of cetane number in diesel fuels [104]. The process uses as raw material the olefins generated in a previous step of thermal and catalytic cracking, which represent a cheaper source of olefins alternative to the currently existing ones. No special details about the conditions applied for the olefin production are indicated, the emphasis being focused on the alkylation step. Alkylation catalysts comprise conventional Lewis... 

Abdul et al. (7) studied the performance of commercially available anionic and nonionic surfactants to clean a sandy soil contaminated with automatic transmission fluid (ATF). Using a batch shaker method, Abdul et al. mixed 5 g of contaminated soil with 100 mL of 0.5% by volume surfactant solution fw min. After the soil settled. 

Dispersant VI improvers are used to a certain extent in engine oils but are more often used in automatic transmission fluids and multipurpose tractor fluids. Incorporating dispersancy into a polymer requires carefully engineered addition of a strongly polar functional group to the base polymer backbone. The most commonly employed functional groups are amines, alcohols or amides. Their mode of incorporation depends largely on the base polymer, and specific details will be described later. 

Utility These products are used almost exclusively in automatic transmission fluids and multipurpose tractor fluids however, these uses are apparently diminishing in favour of polymethacrylate chemistry. 

The severity of different lubricant applications covers a wide shear stability range. Figure 5.8 shows that engine oils are the mildest application, followed by automatic transmission fluids, hydraulic fluids and rear axle lubricants [63]. Thus, matching shear stability requirements of the application with the selection of VI improver is a key formulation consideration. 

Over the years, detergents have found equally important usage in many other types of lubricants, including gear oils, farm tractor hydraulic fluids, automatic transmission fluids and industrial oils. The performance properties that detergents impart to these lubricating fluids include rust and corrosion prevention, improvement in lubricant elastomeric seal compatibility, enhancement of sludge control under oxidative conditions and improvement of wet clutch and wet brake friction level and stability. 

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