2001 Dodge Durango SLT Sport 4.7L V8 - Trans Mod: 45RFE (Automatic)

I am having issues with my vehicle's shifting abilities. I'm experiencing HIGH RPMs before shift. This happens between various gears, but I THINK usually between 3rd and 4th. I usually let off the gas pedal to allow the RPMs to lower and for the tranny to kick into the next gear, before easing back onto the gas pedal to continue accelerating. Sometimes I CAN let off of the gas pedal in-time to allow a smooth shift, however, sometimes I CAN NOT let off in-time due to my music being too loud causing me not to hear the major rev of the engine, which then results in the tranny slamming into the next gear causing a major jerk.



I've noticed that this usually occurs during the following situations:

.Accelerating up inclined or down declined roads.(especially in cruise control)

.Accelerating to quickly switch lanes (sometimes very scary situation when a vehicle is approaching from behind in the desired lane).

.Accelerating right after slowing down for a red-light that had just turned green before I was able to come to a complete stop.

.Accelerating right after yielding(not at a complete stop) for a right turn.


I've done a tone of research on Google and YouTube, which led me to do the following:

.Confirmed a safe Transmission fluid level from tranny dipstick.

.Cleaned Throttle Body and Air intake

.Replaced Throttle Position Sensor

.Replaced Idle Air Control Valve

.Replaced Engine Oil Pressure Switch

.Replaced both Transmission Speed Sensors (Input/Output)
However, all I've noticed is that my engine idles better but I am still experiencing the HIGH RPMs and ugly shifts. This is my family's only vehicle, PLEASE HELP!

 

The problem could be the valve body assy. The side plate is know to snap off the screw heads and cause shifting problems with 3rd and 4th gears.