95 tbird passing gear

I have a 95 tbird 4.6 that I replaced the motor at only 117k mi. After doing so, now the tranny is no longer working properly. When stomping on the pedal, the passing gear does not kick in automatically. I must manually change the gear to get the car to accelerate. BTW, changed the tranny fluid and filter prior to this.

That is really weird...It revs then you have to manually change?

It sounds like an electrical fault. Do you have a check engine light? It could also be your Throttle Position Sensor that is acting up, thus not allowing the transmission to downshift. Get that sensor checked out and see what goes.

I have a 95 tbird 4.6 that I replaced the motor at only 117k mi. After doing so, now the tranny is no longer working properly. When stomping on the pedal, the passing gear does not kick in automatically. I must manually change the gear to get the car to accelerate. BTW, changed the tranny fluid and filter prior to this.
It doesn't rev, if anything, the rpms drop a little.

that sounds like your torque converter clutch solenoid is acting up; if it sticks, it can cause the problem you're having. I'd suggest going to a transmission shop and have them see if there are any fault codes stored and have them look at the data stream to see if there are any irregularities.