1993 Buick Century Owner's Manual - Page 183

Maintenance When Trailer Towing Your vehicle will needservice moreoften when you're pulling a trailer. See the Maintenance Schedule for more on this. Things thatare especially important in trailer operation are automatic transaxle fluid (don't overfill), engine oil, belt, cooling. system, and brake adjustment. Each of these is covered in this manual, and the Index 'will help you find them quickly.If you're trailering, it's a good idea to review these sections before you start your trip. Check periodicallyto see that all hitch nuts and bolts are tight. 181