In the process of doing my snow tire change over on my 1996 850, I found that the lug bolts wouldn't tighten correctly. As I applied torque of 100ft/lbs, gradually in a crisscross pattern, the bolts would almost get to the proper torque, and then kind of crack a little beyond the proper torque. I could apply more torque until they stopped cracking, but then I got concerned that I was essentially applying too much torque. I always clean the bolts with a wire brush before reinstalling them, but I also always wonder if a little lubrication would help them tighten more smoothly without snapping and cracking along the way. I don't like the thought of lubing lug bolts, but maybe just some WD-40 which would dry up afterwards would help. I also always wonder if, after 22 years of service, lug bolts should be replaced as their ability to be torqued properly might be over.

 

With that big tapered base, they really generate a lot of friction compared to my other cars. I do not lubricate mine, but I do notice that it takes an awful lot of torque typically to remove them. It may be okay to experiment with lubrication, but they could loosen, so you might want to recheck them often if you try that. I have had one case where they walked off on one wheel.