Some of the vacuum hoses on my 03 S40 1.9T are old, squishy and cracking. They aren't leaking (yet), but I'd like to replace them. I just can't find anywhere what sizes they are. Any help would be great. I've attached a picture.

 

I am looking for the same specs as well. I discovered today that the plastic elbow into the intake pipe was broken and the hoses are starting to crack. I can find the valves, nipples, and hose clamps on the Volvo parts diagram, but nothing on the hoses or the rubber elbows that look factory made.

 

I just replaces all of those hoses on my 03'. I used 5/16" ID thick walled silicone hose that I found on Amazon. A few tricky curves right next to the throttle body where there is a 90° turn in one of them and the hose almost pinched shut bending it that much. But I just rerouted the hose a bit to have less of a bend in it.