Draw-Tite trailer hitch 24688 was made obsolete in February of 2014 so it is no longer available. But when it was available the installation was the same on sedans and wagons.
The only hitch available now for your 2004 Volvo V40 wagon is Curt hitch # C11822. It also installs the same way on sedans and wagons and is similar to the Draw-Tite hitch.
If you will be using the hitch for towing the correct ball mount to use is # C45521. For a 1-7/8 inch ball use # 19256 and for a 2 inch ball... view full answer...