2003 Buick Regal Owner's Manual - Page 279

7. Remove any rust or dirt from the wheel bolts, mounting surfaces and spare wheel. the places where the wheel attaches to the vehicle. In an emergency, you can use a cloth or a paper towel to do this; but be sure to use a scraper or wire brush later, if you need to, to get all the rust or dirtoff. Rust or dirt on thewheel, L. on the parts to which it is fastened, can make the wheel nuts become loose after a time.The wheel could come off and cause an accident. When you change a wheel, remove any rust or dirt from CAUTION: (Continued) Never use oil or grease on studs or nuts. If you do, the nuts might comeloose. Your wheel could fall off, causing a serious accident. 5-74