2003 Mercury Grand Marquis GS 4.6 V8 from North America


Not a perfect car, but about as dadgum close as you can get!


Plastic intake manifold cracked at 190,000 miles - Fixed myself and replaced the water pump at the same time - Cost $230.

Rear wheel bearing went out at 190,000 miles - Had shop replace both wheel bearings and universal joints - Cost $250.

Other than that, just performed maintenance.

General Comments:

My third Grand Marquis. Have had a 93, a 97, and now this one. The 2003 is the best of the three.

Unbelievable car. Easy to drive. Dead reliable. Easy to fix when something does break. Good on gas for what it is (never had a tank less than 20 mpg, usually get about 25 mpg). Comfortable car.

Not a dragster, but very adequate performance. Absolutely the best deal on wheels.

Would you buy another car from this manufacturer? Yes

Review Date: 24th April, 2012

12th Jul 2012, 22:29

Good review - I love my Grand Marquis too, and it has been nothing but reliable (I actually wrote the review that is below yours). But, as far as the intake manifold, yours is plastic? I thought Ford changed them to metal for the 2003 model year?

24th Nov 2015, 16:49

My 2003 Grand Marquis LS has a composite manifold.

They changed FROM metal to composite for model year 1996, and after the number one coolant crossover kept cracking (resulting in tons of failures and a huge recall that we JUST missed getting a reimbursement on by three weeks for our $730+ repair bill on our 1997 Grand Marquis GS in December 2002), they revised the composite manifolds to include a metal coolant crossover and thermostat housing for model year 2002-2011. These revised manifolds can (and do) still fail, but at a MUCH lower rate than the all-composite units (and usually due to failure of the bond between the composite materials and the aluminum crossover, rather than the composites cracking).

When I re-engined the '97 GS in 2011, I moved that revised manifold over from the '97 engine to a '95 T-bird engine (after a cleaning and thorough inspection, it was in excellent shape). The manifold from the T-bird was one of the all-aluminum manifolds from the Essex engine plant (still have it, with throttle body, injectors and fuel rails, but couldn't use it on the GM, as the throttle body faces the wrong way).

2003 Mercury Grand Marquis GS Convenience 4.6L Modular V8 from North America


An excellent, well-rounded, sedan that is a pleasure to drive, and a popular Mercury icon


Failure of the A/C System - Approx. 66,000 miles. The problem was a broken hose and clamp, resulting a coolant leak. $210 to fix all issues.

Broken driver's-side wiper - 67,215 miles (since replaced). $15 installed at my local dealership.

General Comments:

While many have mocked me for purchasing such a "behemoth" of a vehicle, I have been nothing but satisfied with my purchase of the 2003 Mercury Grand Marquis GS around seven months ago.

Acquired this year through a local dealership, my vehicle came equipped with the "Park Lane" package - granting me the "Convenience Package" features on-top of the ones appointed to you off-the-line from the GS model. To help gauge the reader's interest, I will point out a few major components of the vehicle that will be categorized as follows: Styling, Handling, Power, Interior and Exterior, and Additional Features. Some extra "words to the wise"/notes will also be provided at the end of this review.


You may have noticed, and read from numerous sources, that this vehicle unfortunately has the appearance of a "grandfather car" due to its generally boring exterior and sleeper interior. While it may not be the best thing to look at on the road, it certainly does hold its own, and is very noticeable (especially if you have any additional packages on-top of your initial trim line: such as the Park Lane Edition, which adds a fake vinyl top and various chrome trim-bits to the vehicle). I will go over more elements of the Exterior and Interior styling later on in my review, as they will provide a better glimpse into the detailing and the "feel" of the vehicle than this bit of information will.


The 2003 model of the Marquis has been redesigned to stand out from the previous models, and it shows. Especially when it comes to the handling of the vehicle. As a result of the stiff new structure, the vehicle corners more sharply than previous model years that I have driven - such as the 1999, for example. Re-designed suspension, braking system, and overall poised feel on the road genuinely make this car a pleasure to drive. While it may look like a boat, it certainly doesn't handle like one. The only con that I can note here is that since this vehicle is larger than most on the road, it is a challenge to navigate into smaller spaces. Ever find yourself stuck at a shopping mall and there is that one last space left? Well, unfortunately (and this is arguable) you may need to seek elsewhere for a parking space. Additionally, driving down narrow side-streets or into smaller driveways can be a bit of a challenge (I've come VERY close to whacking the front of my Marquis into my driveway's retaining wall multiple times due to the difficulty of pulling it into the space).


It's got plenty! Powered by the tried-and-trusted Ford Modular V8, this vehicle - regardless of how large it is - has plenty of passing power on the highway, and general power to haul whatever you are storing in the massive trunk that this vehicle comes with. I had once stored over 950 pounds of bagged sand and rocks in my trunk, and loaded a passenger in the front of the vehicle - bringing it near the 1100 pound capacity of hauling additional passengers and cargo (combined), and when I hit the gas, it was almost as if I was hauling air. With over 220 horsepower, I find it much easier to pass traffic on the highway and get to my destinations faster than with my 4 cylinder Toyota. Trust me, you'll feel the difference. But, if you're looking for more oomph - step up to the 2003-2004 Marauder. They're hard to find, but it's worth it once you get one.

However, this model year - in particular - has some notable issues in regards to the powerplant. Specifically: spark plugs. The heads of the plugs will strip if one attempts to remove them, costing more in repairs and labor (if you take your car to a garage or dealer to get it serviced). A family member of mine who owns the same model year Grand Marquis experienced this issue, and it ended up costing him more money to replace the spark plugs.


Interior --- Room is the name of the game, and there is plenty of it. The driver's side is comfortable, and with the power-adjustable pedals (an optional feature that came equipped with my model), it makes driving easier and safer for people of all shapes and sizes. Like many have said, it is basically like driving a recliner around town, and the seats (when properly adjusted to accommodate your personal preferences) give plenty of support for both lumbar and thighs. An 8-way power drivers seat (I have this, but it was an optional add-on) makes driving all the better.

Though, there is not as much rear passenger room as some might expect (maybe because they saved room for the trunk...?). You may also find it hard to rest your arm on the door panel, since it seems to be placed a bit low for my liking (although this is more of a nit-picking personal thing).

And speaking of trunk space, you won't be disappointed. That's because, aside from the Crown Victoria (and possibly the Town Car), the Marquis has the largest trunk space of any car on the American market - over 20 cu. in. worth. It's great for hauling bulk items, such as tons of groceries, large bags (of sand and rocks), and etc. But, as for bulkier items - such as large boxes, it is a bit of a challenge. The seats in the rear do not fold down, and the spare tire, unless once used or removed before hauling something, gets in the way. If you want to haul a smaller patio table - which is still in the box - you may want to bring another car.

Exterior --- As aforementioned, this vehicle has the "grandfather car" image associated with it, which I think is - in some senses - sad. If you choose to get the basic GS package (which is what I have) without any exterior styling features or trims, such as the "Collector Edition" or the "Park Lane Edition", then picking this car out in a crowd may not be as easy. I opted for the Park Lane Edition - which gives me many chrome trim-bits on the outside of the vehicle, a faux vinyl top, and coach lamps; looks better than the "stock" Marquis, but if you're looking for something flashy, this is not the car for you.

I get mocked for driving this around a few times by friends and family. I am 20 years old - and while I may be younger than many of the Marquis owners, I love this car and care for it like it was made of gold. There is nothing I would rather be driving. Plus, I'm not one to be picky about styling!


As I have said before, I opted for the GS Convenience Package with the "Park Lane" trim. This gives me a few extra features than one would normally receive when purchasing the stock GS edition, such as -

- Power adjustable gas and brake pedals

- Traction control

- Power 8-way driver's seat

I'd like to put my "two cents" in just in case someone else was in the market for this type of vehicle. Or, would like to gauge the performance of these features from the perspective of another owner.

Power Adjustable Pedals --- This is an AWESOME feature to have that I have been wanting for a long time. In combination with the power driver's seat, it makes for a truly customizable and enjoyable driving experience. For both myself and others who want to take my car out for a spin. It also gives me some additional safety when driving since, if I am wearing boots during the winter, for example, I can adjust the pedals for the height of the boot - preventing my foot from slipping off the peal (s) or getting caught on the floor mat. If you can find a Marquis with the power pedals, I'd highly recommend it.

Traction Control --- I have mixed feelings about this feature. For dry or wet road conditions (when it is raining), it works well to keep the car on the road and prevent excess wheel spin or a spin-out. However, it is best to leave this feature off during the winter time. I have learned that the excess wheel spin may aide you in some situations during the winter, which will help get this car out of a difficult situation.

Power Driver's Seat --- Again, another excellent feature that I can't live without in my vehicles. The ability to raise, lower, tilt, and slide the seats adds yet another aspect of customization and safety to my driving experience (and anyone else who wants to use the car). Use this in conjunction with the power adjustable pedals, and you're golden.


*Winter Driving* - This vehicle is less than ideal for winter driving. If you need to use this car, which I do, to get around during the winter season, you may want to consider doing the following (I do these things as well) :

- Add studded/winter tires (Studded tires may not be legal in many states. I live in Massachusetts, where they are illegal, and need to use winter tires instead).

- Use tire chains (This will help to add traction to the tires. Though, some have speed limitations and special ratings depending on the type of chain. Check the local mfg. specs).

- Add weight to the trunk (Probably one of the more helpful things you can do, adding around 100-200 pounds of weight will help add traction to the car since it is RWD. I have used cinder blocks and sandbags, but other things can work just as well).

*Discontinuation of the Mercury Brand* - Many may be skeptical about the official discontinuation of the Mercury brand that occurred early (around January) of 2011. The Grand Marquis was the very last Mercury to roll off the line, and you can still fetch Certified Pre-Owned (CP-O) Mercury's for good prices that are under the mfg. original warranty. Additionally, if you are worried about repairs and parts, there is no need to be: Since it is under the Ford umbrella of products, it is still serviceable and parts are plentiful.

UPDATE (8/4/11): *Fuel Economy* - This Grand Marquis grants me an EPA estimated 16/23 (City/Highway), but I seem to get around 17/27. As long as you don't drive the Grand Marquis like a sports car, you should be fairing around the same numbers that I do. Additionally, I recently had my tires Nitrogen-filled at my local dealership; further assisting in greater fuel efficiency.

UPDATE (8/20/11) *The Great Road Trip* - Following the completion of the week-long vacation it was time to head back to Massachusetts. Again, everything went smoothly – the engine kept its cool, there were no issues with the transmission, engine, etc. Within a few hours of travel time the weather started to take a turn for the worst – torrential downpours and the usual thunderstorm started to plague me as I pressed onward. However, I encountered a problem. In the middle of a large downpour, the driver's side wiper came loose from the assembly, resulting in extremely poor visibility during the storm. Granted, these are older wipers and I don't think they were changed often (if at all).

Unfortunately, my troubles were not over. When the storm passed and the temperature started to climb, I reached for the A/C/ knob and turned it to “NORM A/C” and waited a few minutes for it to (hopefully) engage. It didn’t. The system was blowing out warm air. I then went ahead and turned the knob to the “MAX A/C” setting to see if there was any difference. Again, it was useless – the system was still blowing out warm air instead of cold air, and it provided for little relief from the heat. I switched the system to “VENT” and drove the entire length back without air conditioning. This occurred at around the 66,100 mile mark.

UPDATE (10/31/2011) - The A/C system has been fixed. See the "faults" section for more details.

Fuel – According to my Grand Marquis Owner's Manual, it states that for every 400lbs of weight that you carry in the vehicle (passengers and cargo) you can potentially loose 1MPG. Because I was carrying over 400lbs of combined weight I was hardly “efficient” with my consumption of fuel. I had to make frequent stops at the local gas stations. However, since the A/C failed during my return leg of the trip, fuel economy was considerably better. (For those who may be asking- yes, I do have Nitrogen in my tires).

Comfort – I had MORE than enough back, leg, and thigh support for the extent of the trip. I felt like I was driving a recliner all the way to Florida.

Would you buy another car from this manufacturer? Yes

Review Date: 6th July, 2011

7th Jul 2011, 09:34

Actually, the "Park Lane" package was an aftermarket conversion, not a factory package, consisting mostly of a fake convertible top, badges, and some additional trim bits.

19th Jul 2011, 14:19

--Original Reviewer--

Really? I did not know that. Thanks for the information.

29th Jul 2011, 16:03

I'm glad to see another young person like this car. I am 21 years old with a 03 Grand marquis LS Ultimate, with a black cloth top and chrome. I've had it for two years, and love it! Indestructible and comfortable, what more could you ask? Enjoy your car and good luck.

30th Jul 2011, 14:38

These cars weren't offered with a vinyl or cloth top from the factory since the 1991 model as far as I remember. Modern cars just don't look good with these anymore, they just don't have the roof lines. The Grand Marquis does look better than the Town Car with one of these tops, however I think they look a little tacky with them.

31st Jul 2011, 17:03

You are right, they look tacky on the more rounded roofline of late model Mercurys. They looked the part on the more boxier cars of the 80s, none more so than the Town Car and the smaller Chrysler Fifth Avenue IMO.

1st Aug 2011, 23:05

I own a 96 Town Car; black with a black carriage roof, with limo like back window and opera lamps, and it really sets the car off.

4th Aug 2011, 14:38


Thanks for the comments, everyone. I really do love this car, but I also think that the carriage top makes the car look a bit "tacky" at times. And, since you have the covering that stretches over the back windshield, your visibility is a bit skewed - but it's manageable.