I believe the prevailing wisdom is Volvo does not recommend changing the fluid, but it you follow this plan you are doomed to have a failed transmission.

From what I have seen, everyone else (Indy mechanics and DIYers) goes by about 30,000 miles between changes. If the transmission starts behaving a bit erratically (like yours) a change can make a difference.

There are 2 or 3 methods of draining the fluid, chosen by how complete a chage you want. If you search the internet you will find them. The one I chose that didn't involve special equipment involved disconnecting the outlet hose from the tranny at the cooler at the back of the radiator (accessed from the top of the car, right side looking from the front of the car), and putting it via extension tubing into a gallon jug under the car. Then you run the car and the transmission pumps the fluid out. You pump out a quart or two, and then stop and put the same back in via the dipstick tube and an appropriate funnel.

This worked well for me. The only tricky part was disconnecting the fitting at the cooler. It gets a little corroded, and resists separation. No big deal. Just work it gently.

My advice would be look into this. I don't have the site handy I used. Basically just make sure not to pump out more than 1-1/2 quarts before replenishing. Takes about 9 quarts before it runs clear. This is all from memory, so do a little research. Good luck. Don '95 854T 187K

I decided not to flush mine, but I can't tell yuo why other than I couldn't do it myself...