I had this in my '98 V70AWD. It eventually was traced to the universal joint in the passenger compartment at the end of the steering column just before it goes through the firewall. The dealer tried to 'gunked up' the entire joint with a heavy grease that smelled awful, and had planned on replacing the joint for me, but low and behold, on the trip home from the dealer, the squeak went away (two years ago) and never returned. I cleaned off all the extra grease I could find to get rid of the smell. Some of it must have made its way inside the joint parts and killed the noise.