SOCIETY OF AUTOMOTIVE ENGINEERS, INC. 485 Lexington Avenue, New York, N. Y. 10017 The Ford Aluminum Beaker Test: A New Tool for the Study of ATF Oxidation B. A. Pearson and J. L Thompson Ford Motor Co. SOCIETY OF AUTOMOTIVE ENGINEERS Automotive Engineering Congress Detroit, Mich. January 9-13, 1967 670023 Downloaded from SAE International by North Carolina State Univ, Monday, September 17, 2018670023 The Ford Aluminum Beaker Test: A New Tool for the Study of ATF Oxidation B. A. Pearson and J. L Thompson Ford Motor Co. THE EFFECTS OF FLUID OXIDATION on automatic trans­ mission operation can create a variety of problems. Varnish formation quite often means control valve sticking, clutch and band glazing, and similar problems. Sludge formation can lead to oil passage or screen plugging. Acid or peroxide formation may promote corrosive wear of bearings and thrust washers and chemical attack of friction elements, rubber seals and "O" rings. These consequences of oil oxidation have led to exhaustive efforts to find a meaningful test to measure the oxidation resistance of lubricants. Tests have generally fallen into two categories: Those run in actual transmissions and those run in laboratory glass­ ware. However, in some instances automatic transmission fluids have been required to pass oxidation tests run in en­ gines, such as the L-4 test. Seldom did results from different tests agree. Partly for this reason and partly because knowledge of the correlation between laboratory tests and actual oxidation performance in the field was scarce, many concluded that the only way to study automatic transmission fluid oxidation was in the actual transmission. Procedures like the Powerglide, Merco- matic, Dynaflow, and Torqueflite Oxidation Tests were de­ veloped" by various transmission manufacturers. Test operat­ ing conditions were quite similar, as shown in Table 1. Heat lamps and oil coolers with suitable controls were utilized to maintain test temperature. Unfortunately the bench transmission tests did not corre­ late well with one another and in most cases test repeatabil­ ity left much to be desired. Improved reliability has been sought since the origin of these tests and considerable effort on the part of all those interested in automatic transmission fluid oxidation has been expended. One of the more notable efforts was a program initiated in 1957 and completed in 1962 by the Reproducibility Tests Panel of the CRC Power Transmission and Power Steering Units and Fluids Group, which established a more reliable powerglide test method. At Ford, a program was initiated in 1960 to improve the reliability of the Mercomatic test. With the cooperation of Table 1 - Motored Transmission Test Conditions Powerglide Mercomatic Dynaflow Torqueflite Time, hr Temperature, F Speed, rpm Load Other 300 275 1750 None Rev. Stator 300 275 2150 None Rev. Stator 300 300 1750 None Low Gear 300 275 1750 None None ABSTRACT A small-scale oxidation test for automatic transmission fluids has been developed. In the test air flow rates, temper­ ature and catalytic activity can be closely controlled at de­ sired levels. A test procedure for screening automatic trans­ mission fluids is described. Data are presented illustrating the ability of the test to distinguish between different levels of oxidation resistance, the repeatability of the test, and the correlation achieved thus far with a presently used full-scale transmission oxida­ tion test. Downloaded from SAE International by North Carolina State Univ, Monday, September 17, 2018several additive and fluid suppliers, the test variables were either controlled or eliminated and a new Mercomatic test procedure was issued in 1963. This procedure requires a new current model transmission for each test. The transmission is motored at 2150 rpm. A reversed stator is not required since the welded converter is used. A fiberglass insulated heat