Volvo: Volvo transmission, linkage problems, volvo transmission

Question
I have a 1997 Volvo 960. The car drives in neutral and it does not move in
reverse. Took it to a mechanic and he thought it could be the linkage. He
later
said it needs a new (used) transmission. He said the transmission fluid was
"black".  How can I know if the transmission can be fixed rather than changed
(i.e. linkage)?

The cost of replacing the transmission is disproportionate to the value of the
car.

Thank you

Beny  

Answer
Beny,
I have found the case to be that no one has the parts to rebuild those transmissions. When I need a replacement I do one of two things get a used trans or a reman from the dealer. Look at the left side of the trans and get a part number it helps in getting used parts.
Any linkage problems should be seen while inspecting the trans from the bottom.