The Allison transmission cooler lines fix the old leaky transmission lines in your 2006-2010 GM 6.6L Duramax LBZ & LMM. These heavy-duty, high-flow, flexible transmission lines are just what you need for trouble-free performance from your Allison Transmission. Kit Includes: Transmission Lines Concave Washers Includes All Fittings/Hardware Note: In most cases, trucks with aftermarket radiators will require the purchase of aftermarket fittings for installation. Due to the many possible combinations, fitment is not guaranteed on non-stock components.