1997 ram 1500 5.9 wont rev past 2000 rpm

Well, the timing on your ram is computer controlled. is the truck in drive when this mis-fire occurs? or at idle? youve addressed part of your ignition w/the cap-rotor-plug wires. did you examine the old cap for carbon tracking? did you install the rotor properly? i know on my '97 ram the dist is feakin' buried in the engine it would be easy to rotate the rotor while installing/removing it so the timing mark is off. does your engine have the right plugs installed? your plug wires follow the correct firing order with your dist? you did not mention anything about your ignition coil. here is how to safely remove and check your ignition coil. disconnect battery-at the coil disconnect the lead wire (TOP) and primary (BOTTOM) from the coil. label your wires, or take a pic of your ign coil before you remove it so if you forget where the wires go, you have reference point. remove mounting screws and remove coil. clean coil to remove rust/dirt and wipe coil terminals off. inspect case for damage. with a multi-meter, check coil primary resistance by selecting ohm's and then place + and - leads on the pos/neg terminals on the coil, dodge used 2 brands of coils either a "diamond" or a "denso" primary resistance for the diamond mfr'd coil will be between 0.97-1.18 ohms. secondary resistance 11,300-15,300 ohms. Denso primary resistance 0.95-1.20 secondary resistance of 11,300-13,300 ohms. to measure secondary resistance place one of the leads to one the primary terminals and the other lead attatch to the large center terminal. compare your readings to the above values. if your readings are not within range of the above values, your problem is the ignition coil. other causes you may consider is faulty: speed sensor, throttle pos sensor/trans issues like bad pressure solenoid (actuates gear changes) a fault in your overdrive system. hope i have helped!