Page 39 - WHITE BOOK

Research
Ref No FRX 090905 January 19th, 2006 Page Number 5
Property
Viscosity, cSt, 40°C
Water Content
Patch Test for Sludge Content
(Radial Planer Chromatographic Analysisby Fluid Rx)
Power Steering Fluid Limits
Max baseline plus 15% Min baseline minus 20%
0.10%
Acid Number (AN)
Baseline plus 1.0
Visible particles or moderate discoloration or darkening of center of substrate
Particle Count
ISO 21/18/16 max
Automatic Transmission Fluids
Automatic transmission fluidsplay multipleperformanceroles. Thesefluidscool thetransmission components, transfer movement of the torque converter, protect bearings and gear teeth, prevent wear and maintain the correct frictional properties over a wide range of temperatures. Lubricant degradation can be caused by mechanical shearing, oil oxidation, contamination and other causes. Measuring the viscosity at both 40°C and 100°C will allow the viscosity at operating temperatures to be determined. This may be important for certain A TF fluids having kinematic viscosities at elevated operating temperatures close to the 4 cSt limit required to support a dynamic load.
Interval-based Recommendations:
Due to high operating temperatures often greater than 85°C (185°F), common change interval recommendations range from 15,000 miles or once a year (Toyota truck) to 120,000 miles or 6 years (Honda Accord). The most commonly suggested interval by OEMs is 30,000 miles. Amsoil claims their ATFwill last upto60,000miles. Aftermarket articlesrangefrom12,000milesto30,000miles or every one to two years.
Condition-based Recommendations:
Little information on condition-based drain interval recommendations specifically for automatic transmission fluids was located. The OEM specifications do not reference fluid degradation. They specify some typical physical properties requirements.
Automatictransmissionfluidiscomprisedof mineral oil andadditives(occasionallysynthetic).The additives primarily consist of antiwear additives, viscosity improvers and antioxidants. A key measurement of A TF degradation is the loss of the antioxidant additive. When the antioxidant additive is depleted, the oil is subject to oxidation. The oxidation of the base oil increases viscosity, acid and deposits.
Thelimitsbelow for AFT arebasedinpart oncondemninglevelsof mineral-basedhydraulicor compressor fluids and recommended limits including particle counts for A TFs in the laboratory:
The comments and recommendations rendered are for general advisory purposes only and intended for the sole use of Fluid Rx. Distribution of copyright protected items is limited. These services are offered by Noria without warranty or liability as to accuracy or completeness of this information.
Noria Corporation 1328 E. 43rd Court Tulsa, OK 74105 918-749-1400