I have a 1999 S80 T6 that the Volvo dealer tells me needs a new transmission (the check engine light came on, message center sats "transmissin service urgent" and at about 50 mph the tach climbs as the car coasts to a stop). They say this repair will be about $3600. I've fund some used trannies for around $1000. Has anyone replaced the transmissin in an S80? Are there software issues? I've changed out engines and transmissions in the past but the dealer says this ones to tough. Also is there any chance they are wrong and something else might fix the problem (e.g. valve body, flush and change to thicker oil)?

Thanks,

Zach
1999 S80 T6 140K, 1996 960 145K.

Your dealer is probably correct as early S80s did/do have trans issues, especially '99s.
I've replaced several of them myself at our dealer and I can tell you that there's nothing easy about that job, book time runs about 12 hours labor.
There are no real SW issues when replacing one BUT considering the amount of labor to do that job, if you opt for used and it fails soon after its short parts warranty period, you might be out yet another trans with all related charges (at least labor again).
Volvo (GM) did at least fix their problems with their OEM remans as I have yet to see a reman fail and those come with a 1 yr, unlimited mileage parts warranty. A used trans might only have a 30 day or less parts warranty and if it's just another original '99-'00 trans, chances are good that it will also fail.
There is no thicker fluid, chances are that your fluid now still looks good (redish). The failures are due to internal o-rings failing and Volvo doesn't want them overhauled at the dealers, no training either.

Hi My Brother has a volvo s80 which had the same problem. I hope this is the problem on your car. He bought a car and had the same lights came on. He changed the transmission fluid and and thats it, no more problems occured after that. The transmission fluid has to be from the dealer olny. Auto Zone, Kragen and so on, might have the fluid but in dealer it is different kind. After you change the fluid you might need to reset the lights. After they have been reset drive around for a while. This might work. Email me at chernioglo@hotmail.com whats happens. Thanks

Thanks for your info. I think I'll just bite the bullet.

Zach

Thanks for your info. I think I'll just bite the bullet.

Zach