experiencing an 8 second delay when putting the car into reverse. when hot even longer, but when i raise the rpm it kicks into reverse a little quicker and i hear a rush of fluid under the car on the passenger side. all other gears work perfectly, no check engine light, and just did a trans service draining torque and new trans filter. fluid is red and not burnt. what can it be????

There have several mods to valve body for slow engagement but if your trans just started doing this I would think that the reverse clutches(LB3) are worn out.