This is for the first generation S80 cars that use the GM 4T65E automatic transmission.
Volvo says that the fluid in these transmissions is “lifetime.” What does that mean? I think it means just long enough to get out of warranty so that it’s not their problem anymore. These transmissions fail at a very high rate, and I think that not changing the fluid may have something to do with it. I believe that a change interval of about 30,000 miles is reasonable. You need to get that old used-up fluid and shift-clutch gunk out of there and get some fresh fluid in.
Tools and supplies you will need:
Jack and jackstands.
12mm socket and ratchet.
10mm socket and ratchet.
7 quarts of Dexron III or VI ATF.
Disc brake cleaner.
Paper towels or rags.