Depending on the transmission that you have. They have a solenoid kit at Volvo that retails around $500 for the kit. You would need to pay for the labor to install it separate. To be honest with you. If you have at least 100k miles on here you are better off replacing the transmission. The transmission used on the 6 cylinder S-80 do not last more then that. I replaced mine at 109k mile and many others after 100k miles or close to it. Hope this helps and you think about cost wise of doing the solenoid or replacing the transmission. Also if you do not go to a Volvo dealer for the repair, make sure the shop that does the repair whether the solenoid or transmission that they reset the transmission control module adaptation and do the adaptation drive to relearn the gear shifts. Good luck.