Dodge truck engine ECU Up for Sale is a Working, in excellent condition dodge truck engine ECU. My list shows this works with most 1996 3.9 Liter automatic transmission federal emission Trucks. Part number listed at the top or in the large pictures, unit will interchange with-56040803 Check the part number to be sure this is right for your Truck.This unit was runtested & is functional, and offers a 30 day warranty. Please be sure to double check the part number off your original unit before buying. A defective unit is one of the most common no start or random stalling problems with these trucks. They can also be the cause of erroneous check engine lights, cold or hot start problems, or idle control malfunctions. If yours does not have problems, keep an extra ECU in the trunk, you might some day be glad you did... These units are very expensive to buy new. Thanks for looking!