S40 2006
 

I've got a 2006 model in great condition.. But my gearbox seems sluggish.. And revs up weirdly when going downhill. It's an automatic and the manual part of the auto doesn't work anymore .. Need some thoughts on it( and prayers😒) other than that the car is in beautiful condition and 214000 kms on it.one previous owner on it. Well looked after by him and I have done all service and maintenance on it beyond necessary . Just hoping it's not to expensive problem.

First thing I'd do is check the transmission fluid level and color. If it is very dark and has a burnt smell you can try a drain/fill to see if that helps (may need to do 2-3 drains since you only get about 1/3 of the fluid). Then I'd see if there are any fault codes stored in the OBD-II computer. Any other symptoms - ie flashing upshift arrow or tracs light? Sounds like the transmission has downshifted when you lifted the throttle when you go down hill.