X0306 4 2017-11-30 0001137091 POWER SOLUTIONS INTERNATIONAL, INC. PSIX 0001702521 Weichai America Corp. 3100 GOLF ROAD ROLLING MEADOWS IL 60008 0 0 1 0 0001703367 Weichai Power Co., Ltd. SECTION A 197, FU SHOU EAST STREET HIGH-TECH INDUSTRIAL DEV. ZONE WEIFANG, SHANDONG PROVINCE F4 261061 CHINA 0 0 1 0 0001703252 Shandong Heavy Industry Group Co., Ltd. #40-1 YANZI SHAN WEST ROAD JINAN, SHANDONG PROVINCE F4 250014 CHINA 0 0 1 0 Common Stock 2017-11-30 4 C 0 4771248 8.00 A 7700000 I See Explanation of Responses Series B Convertible Perpetual Preferred Stock 8.00 2017-11-30 4 C 0 2385624 0 D Common Stock 4771248 0 I See Explanation of Responses Warrants to Purchase Common Stock 2018-09-30 2018-12-31 Common Stock 4055709 4055709 I See Explanation of Responses 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 benefically owned by the Reporting Persons. Each of the Reporting Persons disclaims beneficial ownership of these securities, except to the extent of its pecuniary interest therein. This Form 4 shall not deemed to be an admission that any Reporting Person hereunder is the beneficial owner of any of the reported securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose. On November 30, 2017, the Issuer entered into a Securities Exchange Agreement with Weichai America Corp., pursuant to which (i) the 2,385,624 shares of Series B Preferred Stock (such shares of Series B Preferred Stock being convertible into two shares of Common Stock for each share of Series B Preferred Stock) held by Weichai America Corp. were exchanged for 4,771,248 shares of Common Stock and (ii) the 2018 Warrant was amended (the "Amended 2018 Warrant") to (a) provide that the Amended 2018 Warrant is exercisable for Common Stock without the requirement to obtain stockholder approval and is not exercisable for Series B Preferred Stock and (b) permit the Issuer to request the accelerated exercise of the Amended 2018 Warrant to the extent required to meet the funding needs of the Issuer. Other terms of the Amended 2018 Warrant as described in the Form 3 filed with the Securities and Exchange Commission by the Reporting Persons on April 10, 2017 remain the same. /s/ Huisheng Liu, Chairman, Weichai America Corp. 2017-12-04 /s/ Sun Shaojun, Executive President, Weichai Power Co., Ltd. 2017-12-04 /s/Jiang Kui, President, Shandong Heavy Industry Group Co., Ltd. 2017-12-04