UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT PURSUANT

TO SECTION 13 OR 15(D) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported): September 19, 2025

AMERICAN AXLE & MANUFACTURING HOLDINGS, INC.

(Exact Name of Registrant as Specified in Its Charter)

Delaware

(State or Other Jurisdiction of Incorporation)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

¨    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨    Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

On September 19, 2025, American Axle & Manufacturing Holdings, Inc. (NYSE: AXL) (“AAM”) announced that its wholly-owned subsidiary, American Axle & Manufacturing, Inc., has priced its previously announced private offering of $850 million in aggregate principal amount of 6.375% senior secured notes due 2032 (the “Secured Notes”) and $1.25 billion in aggregate principal amount of 7.750% senior unsecured notes due 2033 (the “Unsecured Notes,” and together with the Secured Notes, the “Notes”). The offering of the Secured Notes was upsized from the previously announced $843 million in aggregate principal amount and the offering of the Unsecured Notes was upsized from the previously announced $600 million in aggregate principal amount. The offering is expected to close on October 3, 2025, subject to customary closing conditions.

A copy of the press release of AAM is filed as Exhibit 99.1 hereto. The press release is incorporated herein by reference in its entirety.

Forward-Looking Statements

This report may contain statements concerning our expectations, beliefs, plans, objectives, goals, strategies, and future events or performance, including, but not limited to, the statements about the offering of the Notes, our intention to issue the Notes at the closing, the expected use of proceeds and the Combination. Such statements are “forward-looking” statements within the meaning of the Private Securities Litigation Reform Act of 1995 and relate to trends and events that may affect our future financial position and operating results. The terms such as “will,” “may,” “could,” “would,” “plan,” “believe,” “expect,” “anticipate,” “intend,” “project,” “target,” and similar words or expressions, as well as statements in future tense, are intended to identify forward-looking statements. Forward-looking statements should not be read as a guarantee of future performance or results, and will not necessarily be accurate indications of the times at, or by, which such performance or results will be achieved. Forward-looking statements are based on information available at the time those statements are made and/or management’s good faith belief as of that time with respect to future events and are subject to risks and may differ materially from those expressed in or suggested by the forward-looking statements. These risks and uncertainties related to AAM include factors detailed in the reports AAM files with the Securities and Exchange Commission, including those described under “Risk Factors” in its most recent Annual Report on Form 10-K and its Quarterly Reports on Form 10-Q. It is not possible to foresee or identify all such factors and we make no commitment to update any forward-looking statement or to disclose any facts, events or circumstances after the date hereof that may affect the accuracy of any forward-looking statement.

(d) Exhibits

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.