Transmission only goes in reverse - 1992 Ford Crown Victoria

auto transmission -check the reverse servo/ solenoid operation
manual transmission--check for loose selector fork for reverse , broken selector fork, stripped reverse gear, reverse gear key failure

Most likely you have a linkage problem between the shift lever and the transmission and or the rubber bushings for that linkage are bad. It can also be the pivot point of the shift lever.

Check the shift linkage. It is either loose or binding and not engaging reverse. It could also be the reverse clutch pack you just rebuilt or replaced.

Perhaps it is in severe pain, because you failed to identify it it by make and model!

Servo or band worn out, o.ring gone hard or clutch pack burnt out.

4l60e or 4l80e transmission?

First thing I would suggest is, you check the transmission fluid level in your car. If your fluid level is adequate, then you may need to have your transmission bands adjusted or gears and/or clutches within your transmission replaced.

After reading your question again, I am unsure if you shifter will not engage reverse or the transmission will not go into reverse. Nevertheless, if the transmission will not go into reverse, even after the car warms up, then your transmission may require a serious overhaul. Try driving your vehicle for several miles and see if it goes into reverse after warming up.

p0705 is the transmission range sensor which tells the ECM what gear the transmission is in neutral/reverse. Which was probably happened when you lost Drive gear

check fluid if it is a dark color and stinks transmissions probably needs rebuilt sounds like low reverse or direct clutch is bad trna will still go into loe by using forward clutch if low reverse is bad shoul be having problems with 3rd or direct in forward if forward clutch is bad

Check the linkage. Set the parking brake, and examine the transmission where the linkage connects to the actuator on the transmission, and have somebody operate the shift lever. Take note if the transmission is going into reverse or not and if the actuator on the transmission is always going to the same spot.

If this test does not reveal a problem, disconnect the linkage from the actuator, and move the actuator by hand to the reverse position. you should feel it fall into the reverse position. If it does fall into the reverse position, and the transmission fails to go into reverse, then take it to a transmission shop