Repair, Upgrade or Replace your Allison transmission with high quality parts from DHD. For 15 years Dirty Hooker Diesel has been a leader in Allison transmission upgrades and repairs. DHD stocks Allison transmission parts from leading manufactures like DHD, Raybestos, TCS, Suncoast, Allison, Goerend, Precision and Alto. Need help making some decisions? Give us a call @ 989-479-0444.