On my 94 Volvo N/A 940 with AW-71L, the shift points are (IMHO) too close together between shifting into OD (4th speed) and the torque converter locking (5th speed).
As it is, driving on a road with a lot of inclines, the transmission spends very little time in OD.
This is like shifting from 5th gear into 3rd gear in a standard shift transmission.
The engine is either in a strain, or revving too high.
It seems like 1st to second gear and on into 3rd gear is OK.
At that point it will shift into OD at 45MPH, and the torque converter will follow closely, locking at 50 MPH....unless the accelerator is kept depressed and the car is accelerating quickly.
If I'm climbing a long steep grade, lack of HP prevents the car from accelerating when the converter is locked. This is simply a matter of engine horsepower verses engine load.
If the throttle is increased the transmission downshift will cause the transmission to simultaneously unlock the torque converter and shift out of OD.
This in effect shifts the overall gear shift from 5th to 3rd, and totally bypasses 4th (OD).
The engine is either lugged down, or it is revving higher than is required to increase the speed of the car.
It's a big jump in engine RPM.
I would disconnect....turn off....eliminate.... the locking feature of the torque converter if I could. No, I'm not going to swap it out...., just belly aching.
If all of my driving was on a flat road, it would be OK.
Too bad that Volvo didn't design some type of adjustment on the locking function in the torque converter.