This specification describes the requirements of low permeating fluorocarbon elastomer seals with good resistance to fuel and fuel/alcohol blends. 

Material Description.

To fully describe the material, a type must follow the specification number. Type I - Fluorocarbon Elastomer (FKM containing 67 wt% Fluorine) with -20 °C low temperature flexibility. Type II - Fluorocarbon Elastomer (FKM containing 70 wt% Fluorine) with -5 °C low temperature flexibility. 

Symbols.

Not applicable. 

Applicability.

This specification is applicable to fuel sender seals. 1.4 Remarks. In addition to the test requirements listed in this specification, additional testing may be required for validation of the seal used in the sender closure Module Reservoir Assembly (MRA). Satisfactory completion of those validation tests, as defined by the GM Materials Engineer, must be demonstrated prior to approval to this specification.