2004 Mercury Grand Marquis

2004 Mercury Grand Marquis

Overview

The 2004 Mercury Grand Marquis, a full-size rear-wheel-drive sedan, is generally considered a reliable vehicle, particularly known for its robust powertrain and comfortable ride. Built on the Ford Panther platform, it shares many components with the Ford Crown Victoria and Lincoln Town Car, benefiting from years of refinement. While it excels in durability and ease of maintenance, like any vehicle of its age, it can experience specific issues. This analysis focuses on common mechanical and electrical concerns reported by owners, excluding routine maintenance and normal wear and tear, to provide a clear picture of its long-term reliability.

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Engine

4.6L V8 (2V)

Intake Manifold Gasket Leaks

• Symptoms: Coolant leaks, engine misfires, overheating, sweet smell of coolant.
• Solution: Replacement of the intake manifold gaskets.
• Cost: $400 - $700

Spark Plug Blow-Out

• Symptoms: Engine misfires, rough idle, loss of power, ticking noise from engine.
• Solution: Requires specialized tools for extraction and replacement, often with updated spark plugs or inserts.
• Cost: $500 - $1000

Transmission

4R70W 4-Speed Automatic

Torque Converter Shudder

• Symptoms: Vibration or shuddering during acceleration, especially at lower speeds.
• Solution: Transmission fluid flush and filter change, or replacement of the torque converter.
• Cost: $300 - $800

Slipping Gears

• Symptoms: Delayed engagement, difficulty shifting, engine revving without acceleration.
• Solution: Transmission fluid and filter replacement, or internal transmission repair/rebuild.
• Cost: $800 - $2500+

Suspension

Standard Chassis

Ball Joint Wear

• Symptoms: Clunking noises from the front end, uneven tire wear, steering instability.
• Solution: Replacement of worn ball joints.
• Cost: $300 - $600

Air Suspension Compressor Failure (if equipped)

• Symptoms: Vehicle sagging, inability to adjust ride height, compressor not engaging.
• Solution: Replacement of the air suspension compressor.
• Cost: $500 - $900

Electrical

Body Control Module (BCM)

Intermittent Electrical Gremlins

• Symptoms: Malfunctioning power windows, door locks, interior lights, or dashboard indicators.
• Solution: Diagnosis and potential reprogramming or replacement of the BCM.
• Cost: $400 - $800

Alternator

Premature Failure

• Symptoms: Dimming headlights, battery warning light, difficulty starting, dead battery.
• Solution: Replacement of the alternator.
• Cost: $300 - $600

Exterior

Body Panels & Trim

Clear Coat Peeling

• Symptoms: Chalky appearance on paint, peeling clear coat, especially on horizontal surfaces.
• Solution: Repainting affected areas.
• Cost: $500 - $2000+

Headlight Lenses

Clouding/Yellowing

• Symptoms: Reduced headlight visibility, hazy or yellowed appearance.
• Solution: Headlight restoration kit or replacement of headlight assemblies.
• Cost: $100 - $400

Interior

HVAC System

Blend Door Actuator Failure

• Symptoms: Inability to control temperature (stuck on hot or cold), air only coming from certain vents.
• Solution: Replacement of the blend door actuator(s).
• Cost: $200 - $500

Seat Upholstery

Wear and Tear on Driver’s Seat

• Symptoms: Cracking, tearing, or excessive wear on the driver’s seat bolsters and cushion.
• Solution: Repair or replacement of seat upholstery or the entire seat.
• Cost: $300 - $800

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Summary Verdict

The 2004 Mercury Grand Marquis is a solid choice for those seeking a durable and comfortable full-size sedan. Its primary strengths lie in its robust 4.6L V8 engine and reliable transmission, which are generally trouble-free with proper maintenance. Common issues tend to be related to age and mileage, such as intake manifold leaks, spark plug issues, and torque converter shudder. Suspension components like ball joints can wear out, and electrical gremlins, often linked to the BCM or alternator, are not uncommon. Exterior paint and interior wear are also typical for a vehicle of this vintage. Overall, the Grand Marquis offers good value and can remain a dependable vehicle with attentive maintenance and addressing specific known issues.