SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
	Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person* Weichai America Corp. (Last) (First) (Middle) 3100 GOLF ROAD (Street) ROLLING MEADOWS IL 60008 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol POWER SOLUTIONS INTERNATIONAL, INC. [ PSIX ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 09/10/2025
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	09/10/2025		S(1)		6,308	D	$90.2846(2)	10,709,844	I	See Explanation of Responses(8)
Common Stock	09/10/2025		S(1)		5,018	D	$91.4429(3)	10,704,826	I	See Explanation of Responses(8)
Common Stock	09/10/2025		S(1)		14,557	D	$92.3398(4)	10,690,269	I	See Explanation of Responses(8)
Common Stock	09/10/2025		S(1)		2,515	D	$93.5023(5)	10,687,754	I	See Explanation of Responses(8)
Common Stock	09/10/2025		S(1)		7,585	D	$94.4505(6)	10,680,169	I	See Explanation of Responses(8)
Common Stock	09/10/2025		S(1)		571	D	$95.1956(7)	10,679,598	I	See Explanation of Responses(8)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* Weichai America Corp. (Last) (First) (Middle) 3100 GOLF ROAD (Street) ROLLING MEADOWS IL 60008 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Weichai Power Co., Ltd. (Last) (First) (Middle) SECTION A 197, FU SHOU EAST STREET HIGH-TECH INDUSTRIAL DEV. ZONE (Street) WEIFANG, SHANDONG PROVINCE F4 261061 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Shandong Heavy Industry Group Co., Ltd. (Last) (First) (Middle) #40-1 YANZI SHAN WEST ROAD (Street) JINAN, SHANDONG PROVINCE F4 250014 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. These transactions occurred pursuant to broker-dealer sales conducted in accordance with Rule 144 under the Securities Act of 1933, as amended.

2. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $90.00 to $90.99, inclusive. The Reporting Persons (as defined below) undertake to provide the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares of Common Stock sold at each separate price within the range set forth in this footnote.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $91.00 to $91.99, inclusive. The Reporting Persons (as defined below) undertake to provide the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares of Common Stock sold at each separate price within the range set forth in this footnote.

4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $92.00 to $92.98, inclusive. The Reporting Persons (as defined below) undertake to provide the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares of Common Stock sold at each separate price within the range set forth in this footnote.

5. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $93.12 to $93.95, inclusive. The Reporting Persons (as defined below) undertake to provide the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares of Common Stock sold at each separate price within the range set forth in this footnote.

6. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $94.02 to $94.88, inclusive. The Reporting Persons (as defined below) undertake to provide the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares of Common Stock sold at each separate price within the range set forth in this footnote.

7. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $95.03 to $95.58, inclusive. The Reporting Persons (as defined below) undertake to provide the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares of Common Stock sold at each separate price within the range set forth in this footnote.

8. This report is filed jointly by Weichai America Corp., Weichai Power Co., Ltd. and Shandong Heavy Industry Group Co., Ltd. (collectively, the "Reporting Persons"). Weichai America Corp. is the direct owner of the Common Stock referenced in this report and shares the power to vote and the power to dispose of all of such shares of Common Stock with the other Reporting Persons. No individual has beneficial ownership over the Common Stock beneficially owned by the Reporting Persons.

Remarks:

Exhibit List: Exhibit 24.1 - Power of Attorney (Weichai Power Co., Ltd.), incorporated by reference to Exhibit 24.1 to the Form 4 filed by Reporting Persons with the Securities and Exchange Commission on August 14, 2025 Exhibit 24.2 - Power of Attorney (Shandong Heavy Industry Group Co., Ltd.), incorporated by reference to Exhibit 24.2 to the Form 4 filed by Reporting Persons with the Securities and Exchange Commission on August 14, 2025

	/s/ Jinguang Liu (aka Jin Liu), Chief Financial Officer, Weichai America Corp.	09/12/2025
	/s/ Chenglong Sun, Authorized Representative, Weichai Power Co., Ltd.	09/12/2025
	/s/ Chenglong Sun, Authorized Representative, Shandong Heavy Industry Group Co., Ltd.	09/12/2025
	** Signature of Reporting Person	Date
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