Check the listing for details. . NEW Allison AT545/MT640/MT643 Transmission Electronic Modulator. Condition: New. Listed at 539.91 USD. Allison AT545 / MT630 / MT643 Transmission Electronic Modulator for Large Vehicles and Trucks Original Equipment Part No: 29508036 This is a brand new never installed item, the photos usually show the actual products to be shipped.This part may fit other models not listed. New transmission electronic modulator for Allison AT545 / MT630 / MT643 transmissions. This actuator modulator is used in modern school buses, Blue Bird Buses, GMC Topkick, Chevy Kodisk and lots of other rear wheel drive truck applications with Allison AT and MT series automatic transmissions. Modern Allison transmissions use this style of electronic actuator modulator instead of the vacuum style modulator. Transmissions that do not shift properly can be tested and/or repaired with this new original equipment actuator modulator. MADE IN THE U.S.A. **FREE SHIPPING** (** continental United States Only)Another quality product brought to you by Transmission Jobber Supply! Not quite what you're looking for? Check out more of our ready to ship, on hand items in the TJS stock. Visit The Transmission Jobber Supply eBay Store All of our items listed are on hand, ready to ship! Customer service is our number one priority, email us any questions! We offer combined shipping for multiple purchases to export customers.Transmission Jobber Supply appreciates the opportunity to serve your transmission parts needs. Powered by eBay Turbo Lister The free listing tool. List your items fast and easy and manage your active items.