* 3.9L V6: This was a fairly common choice.
* 5.2L V8: A popular and more powerful option.
* 5.9L V8: The largest engine typically offered.
To know the exact engine size in *a specific* 1989 Dodge Ram Van, you'd need to check the vehicle's documentation (owner's manual, vehicle identification number (VIN) decoding) or look at the engine itself (the displacement will be stamped on it).
