The conversion process from a Powerstroke to a Cummins diesel engine varies slightly depending on the year of the vehicle and size of the engine. Differences in the fuel delivery system, type of transmission and the battery voltage will determine the type of kit purchased. Cummins engine(s) will fit just about any transmission, as long as the correct adapter plate is used. Another concern would be emissions output. When deciding on the size and year of the Cummins engine, it is wise to select one that matches the year of the vehicle, or newer.
When converting older vehicles, earlier than 1999, additional work will be needed. A fuel delivery system that can pose conversion problems, due to the scarcity of necessary parts, is the mechanical-diaphragm style fuel pump. Electronically controlled transmissions require the use of a throttle position sensor, which is a part that is hard to come by. Other areas one needs to pay attention to are the fan-support and thermostat housing, vacuum pump and AC pump (compressor). These components may require modifications to brackets and mounts, or the replacement of the component with one that matches the Cummins engine.
Common Rail fuel systems are found on vehicles built from 2003 to 2006, and they do not require the Dodge PCM to operate. However, the ECM (engine control module), typically mounted to the side of the engine, will be needed. The ECM will need to be re-flashed because the SKIM (security key immobilizer module) could prevent the engine from operating in a new vehicle. This needs to be performed before you reach the start-up testing point. Vehicles built in early 2003 that have manual transmissions could get around this problem by incorporating the Dodge SKIM module and having it reprogrammed by a locksmith.
Conversion kits will include detailed instructions specifically tailored toward the year of the vehicle and the year/model engine that will be transplanted. Packages include transmission adapters (for those selecting to use their Ford transmission), motor mounts (with insulators) and adapters designed to assist in maintaining the original dash. Depending on the selection, the kit will also include a transmission controller harness, intermediate harness (to mate the Cummins engine to its new vehicle), ambient temperature sensor, bushing kit, tach mount, tach sensor, tach ring, cruise control servo and cable, and a gas version pedal to replace the electronic throttle pedal.
Conversions to 1999 and newer vehicles are physically the easiest to perform due to abundant under-the-hood room. All the components mounted to the Cummins engine will be retained and used. Before installing the engine, new motor mounts need to be installed, along with an alternator regulator, transmission bushing kit and tachometer (if applicable). The stock radiator and the intercooler can both be used. The transmission will only need to be modified if using the original Ford transmission. The bell housing may also need to be trimmed because the Cummins starter will ride higher than the original. 12-volt Cummins engines are non-electric and need no additional wiring; however, 24-volt engines will require the supplied harness.
Decide on the engine and transmission particulars before selecting your kit, and the task will go smoothly.
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