The manual for my 2016 V60 says this for tires that can be used:

235/40/18 or 235/45/18

When I bought the car it had 235/40/18 on them and that's darn low profile for me and my wife pain from chemo felt every bump. Recently went to 235/45/18 as per manual allowance. That extra bit of air, a cushion between me and the road helps. I don't care about flying through corners, I am in my 70's and those days are gone.

The problem is that the with a bigger aspect ration, my speedometer will be off a bit. Not much because I didn't change that much height.

Called Volvo to see about getting a computer update to calibrate the speedo. I was told the only thing they have is a software update if you change the wheels to a different size. Ok guys, that means you have software that calibrates for a different wheel/rim which means different diameter. Changing the aspect ratio does the same thing --- changes diameter. Service department said, yes I understand you but we only have software that can do this for a wheel/rim change.

I really don't want to get a speeding ticket for the difference of maybe 1.5 > 2 MPH difference in speed. Any ideas.