My dad used to have a 1997 Mercury Grand Marquis. I remember the trunk was huge, and with the 4.6-liter engine, it got decent gas mileage for a big car. The manual said the belt should be checked at 100,000 miles for normal service and then checked every 20,000 miles after that. When dad decided it was time to change the belt, we did it together.
Dad used a 1/2-inch-drive breaker bar to rotate the tensioner arm so I could slip the belt off the pulleys. After I positioned the belt on all the pulleys except for the alternator, dad rotated the tensioner again while I slipped the belt onto the alternator pulley.
