GENERAL MOTORS COMPANY and THE BANK OF NEW YORK MELLON, as Trustee EIGHTH SUPPLEMENTAL INDENTURE Dated as of May 7, 2025 to INDENTURE Dated as of September 27, 2013 5.350% SENIOR NOTES DUE 2028 5.625% SENIOR NOTES DUE 2030 6.250% SENIOR NOTES DUE 2035