One problem related to rear seat belt has been reported for the 1998 Mercury Mountaineer. The most recently reported issues are listed below.
While the child was in the booster seat, the seat belt was too tight. When the consumer tried to loosen the belt, it became so tight, the consumer had to cut the seat belt in order to get the child out.
| Front Seat Belt Buckle Assembly problems | |
| Rear Seat Belt problems | |
| Front Seat Belt Webbing problems |