Abstract: A curable fluoroelastomer composition comprising: (A) fluoroelastomer gum comprising interpolymerized, repeating units derived from vinylidene fluoride, tetrafluoroethylene, and copolymerizable hydrocarbon olefin, (B) polyhydroxy compound, (C) organo-onium compound, and (D) fluoroaliphatic sulfonyl compound adhesion promoter, where the amount of fluoroaliphatic sulfonyl compound in the elastomeric composition is sufficient to result in greater adhesion of the elastomeric composition, after curing, to an inorganic surface coated with a primer composition comprising aminosilane compound, than can be achieved between an elastomeric composition comprising (A), (B), and (C), after curing, and an inorganic surface coated with said primer composition comprising aminosilane compound.