I bought my 04 Grand Marquis LS used in 2005 with about 17000 miles on it, and since it just turned 75000 miles, I feel I can give and honest opinion of the car. It's comfortable for short or long trips. No major repairs or breakdowns - even the brakes are original. It's still tight, no rattles. Gas mileage is a solid 17 around town and 26-28 on the open road. Not bad for a large car. Merc specifies semi-synthetic oil but since I change it myself, I switched to full synthetic oil after the first change. The transmission fluid was changed at 65000 miles. There are no driving issues and the car still looks and drives like new. I've read some other reviews and I have experienced and corrected some of the minor problems the reviewers mentioned. Engine noise - I experience a high level of engine noise that turned out to be 2 broken catalytic converters. Both were covered by the 80,000 mile manufacturers warranty. I also found that this engine and all other engines will run quieter and more fuel efficiently with a top-oil fuel additive with every fill-up. I've not been a fan of additives, but this one actually worked. Squeaking from the front end - a little grease applied to the adjustable hood bumpers cures this problem. Stiff ride - Mercury redesigned the suspension of the shock and coil spring version of the GM in 2003 and the ride is much stiffer than previous years. Some will appreciate the "sports car'" feel, but not me. I decided to replace the original rear shocks and front struts with aftermarket replacements and the results were good. Some brands of tires are made for the larger cars and advertise a softer ride. Don't be tempeted to soften the ride by running less than 32-35 PSI in your tires. The car handles better with fully inflated tires and the gas mileage is also better. Sagging rear end - Four large adult passengers and a trunk full of luggage made the rear end sag more than I wanted, so I replaced the rear coil springs with a "variable rate" coil spring that doubles the weight carrying capacity (1200 lbs vs 600 lbs) while giving me a good ride. I liked the new coil springs so well that I also installed them on my wife's Chevy Venture van and eliminated the troublesome air leveling shocks. I will have my Grand Marquis for a long time.