One problem related to sway bar has been reported for the 1998 Mercury Grand Marquis. The most recently reported issues are listed below.
During normal driving, heard extremely alarming loud creaking, squeaking noises from front end. Steering became sloppy and erratic. Took it to r&r automotive in lex. Pk. Md and had complete front end replaced, due to worn out ball joints, idler arms, pitman arms, tie rods, sway bar ends which could not be lubricated. Replaced with those equipped with grease fittings. $1750. 00.