Required for the assembly of iron-sulfur (Fe/S) clusters in mitochondria (By similarity). Assisted by the DnaJ-like co-chaperone jac1 and the nucleotide exchange factor mge1, it mediates ATP-dependent Fe-S cluster transfer from the scaffold proteins isu1/isu2 to grx5 (By similarity). Essential component of the PAM complex, a complex required for the translocation of transit peptide-containing proteins from the inner membrane into the mitochondrial matrix in an ATP-dependent manner (By similarity). Constitutes the ATP-driven core of the motor and binds the precursor preprotein (By similarity). ATP + H2O = ADP + H(+) + phosphate Interacts with the Fe/S cluster assembly and transfer machinery (By similarity). Component of the PAM complex (By similarity). Up-regulated when grown with elevated levels of potassium chloride. Belongs to the heat shock protein 70 family.