Volvo: Volvo so 80 t6 trany, repair attempt, limp home

Question
2000 S80 T6 4 speed auto 96,000 miles
My trany won't shift into 4th. I get a code says shift selinoid stuck off. took it dealer had software upgrade. That did get help so it would shift manualy. (kinda) If I leave it in manual mode I can shift 1st, 2nd, 3rd, then when I shift to 4th dash indicator says 4 but tranny doesn't shift then goes in to limp home mode. (stuck in 3rd) When I shut off the car and restart, it resets so I can shift manually again.

Have talked to 4 dealers differnt story from each one. One selinoid needs replaced. I need a whole selinoid pack $900 or could be valve body. One even said drive it for a week so software had time to reset. Last on said needs whole trany rebuild $4500
Have checked fuild not low or burned, added lucas and unhooked battery for 15 minutes to reset. New battery no low voltage.

Thanks
Robert  

Answer
Hello Robert! My experience with that fault would lead me to replace the transmission. It is the only permanent fix. Any other repair attempt will only mask the problem for a while. It is best to replace the tranny. I am very suprised a dealer would not have done that in the first place.

Jimmy