Hi I have a 96 RAM 5.9L which is showing its age. I am wondering what is the differences between years for the 5.9L engine. I would like to go as new as possible and with as low mileage as possible but would like to know what engine would still use the same wiring harness/PCM/transmission. Also will 5.9's from the 3rd gens work? Your help is greatly appreciated.

 

The basic 5.9 litre Magnum engine is unchanged across years. It is your vehicles ECM, wiring harness, and transmission that will be used. The block and heads on the 5.9 Magnum are unchanged so you can use any year engine. That being said, you may need to use your attachments: oil pan, intake manifold, throttle body, crankshaft damper, flex plate, etc to make sure the install goes smoothly.

 

The only thing, that I know for sure. Dodge changed the spark plugs in 98. Federal Mogul informed me you can put 97 plug in a 98-BUT not a 98 plug in a 97.
The 98 plug is a lot longer than a 97. I think it was for emissions.