Automotive engineers cannot afford to take chances with materials used for vehicles in commercial production. Longer warranty periods, the severe cost penalties of component failure and model recalls have made automotive materials specifiers highly risk-averse. That's why, when a component is selected for use on production models, it has survived exhaustive testing and comparisons to alternatives.

DuPont^TM Vespel® parts are perfect examples of components that have earned the trust of many demanding automotive engineers and designers, following years of service in thousands of applications. As a result, Vespel® thrust washers, seal rings, bushings and other vital friction and load bearing parts are widely specified by the automotive industry.

Vespel® SP-21 thrust washers located between the aluminum die cast case and second clutch at right of JATCO 7-speed automatic transmission, replace larger, heavier metal thrust needle bearings to save weight and space, and enhance fuel efficiency.

Vespel® SP-21 thrust washers are thinner and lighter than comparable metal thrust needle bearings. In addition, they can rotate directly against the aluminum housing, allowing a reduction in the number of parts, and easier assembly. These advantages helped engineers at JATCO reduce the overall size and weight of the AT unit.

Weight and space saving were not the only reasons. Vespel® SP-21 parts can withstand pressure velocity (PV) loads of up to 40 MPa m/s in lubricated applications, and offer an exceptionally low coefficient of friction, leading to lower friction losses than alternative polymer solutions.

The current 7-speed AT from JATCO is fitted to the Nissan Fairlady Z, Skyline, Fuga, and the Infiniti FX50 and EX37, enhancing the driving pleasure for these luxury rear drive vehicles. The light, compact unit occupies little more space than a 5-speed automatic transmission, while delivering improved fuel efficiency by reducing friction. Its multi-staged gear ratios and increased transmission ratio range offer improved startup and mid-range acceleration, plus enhanced smoothness and quietness at high speeds.

Vespel® SP-21 thrust washers.

• No melting point - the washer will not melt.
• High limiting PV value (an indicator of resistance to wear) - superior to other engineering resins.
• Low wear rates - exceptional wear resistance in contact with lubricated aluminum components, even with foreign matter in the oil.
• Custom-designed oil grooves - allow precise control of oil flow, and further enhance resistance to wear.
• Very low coefficient of friction - oil film forms easily on washer surface, leading to low friction losses, low wear, lower heat generation.
• Superior heat resistance - Vespel® parts can easily handle typical transmission operating temperatures of -40°C to +180°C.

SPECIAL NOTE:The information set forth herein is furnished free of charge and is based on technical data that DuPont believes to be reliable. It is intended for use by persons having technical skill, at their own discretion and risk. Handling precaution information is given with the understanding that those using it will satisfy themselves that their particular conditions of use present no health or safety hazards. Because conditions of product use and disposal are outside our control, we make no warranties, express or implied, and assume no liability in connection with any use of this information. As with any material, evaluation of any compound under end-use conditions prior to specification is essential. Nothing herein is to be taken as a license to operate or a recommendation to infringe on any patents. While the information presented here is accurate at the time of publication, specifications can change.

CAUTION: Do not use in medical applications involving permanent implantation in the human body. For other medical applications, discuss with your DuPont representative and read Medical Caution Statement H-50102.