New transmission for 2001 Volvo S80

Before you replace the tranny update the TCM's software, get a complete fluid flush, reset the fluid counter in the TCM and re-adapt the transmission. (need Vida or Dice diagnostics) If you did all this don't waste more time and money on it. If you replace the tranny, make sure a Volvo specialty shop does it because the TCM has to be re-programmed which also required Vida / Dice. Zee

I agree with the other answer but add that a glycol test should be performed as well to verify what caused the issue but would not flush the fluid if it looks to be in good condition. Also pull codes as certain codes will tell you whether the transmission can be saved or not...