GMNA 9984164 PDF

This specification covers the materials and performance requirements for coatings for application on vehicle suspension coil springs. The coating is intended to provide surface damage tolerance and corrosion resistance.

Typical Application. The type of coatings covered are described below:

Type I - Waterborne, Cathodic Electrodeposition Coating or Powder Coating

Type II - E-Coat + Polyethylene Powder Coating

Type III - Polyester Powder Coating

Type IV - Coating for High Strength Coil Springs

Note: Type IV coatings are to be used on coil springs made from a steel whose maximum tensile strength exceeds 1880 MPa for cold coiled springs or a surface hardness exceeding 52 HRc for hot coiled springs. For any parts that do not exceed the Type IV criteria, any of the coating types are acceptable. If no coating type is designated on the part drawing, then Type I is implied, unless the Type IV criteria is exceeded.