I'm in the process of debugging a new (to me) 2000 V40 with 80,000 miles. Car has some vibration around 60 mph. I've had the wheels balanced but the vibration remains. There's some side to side play in the passenger side inner CV joint, but there's also up-down slop in the driver's side driveshaft at the transmission. When I grab the driver's side inner CV joint it rotates up and down a little. I'd expect this to be rock solid. Is something broken inside the transmission?

 

if you have weight off the wheel (suspension drooping) all that is normal. Check balance in the tires.

 

Thanks for responding. Wheels are balanced. My investigation of the driveshafts was with wheels on the ground (ramps, actually).

Here's what I don't understand. How's it possible for the driver's side inner CV joint - the cage - to rotate up and down? It's engaged solidly into the differential, which means something in the differential is also rotating up and down slightly. What's in the differential that will do that?

Or is it that the splines on the driveshaft are worn allowing the inner CV joint to slop up and down?