How reliable is a 2004 Ford Mustang?

The 2004 Mustang, the final year of the fourth-generation New Edge styling, can still be a dependable used car if you buy a well-preserved example and keep up with maintenance. Overall reliability sits in the average range for its age, with notable variation by model and maintenance history.

This article examines what affects reliability across the 2004 Mustang lineup, common issues reported by owners, ownership costs, and practical tips for evaluating a used car from this era.

Overview of the 2004 Mustang lineup

In 2004 Ford offered several variants based on the SN95/New Edge platform, including the base V6 model and the GT with a V8, plus limited-run performance versions such as Mach 1 and, in some markets, the SVT Cobra. The 2004 lineup blended traditional Mustang appeal with some chassis and interior updates, but as a 20-year-old used car, reliability outcomes depend heavily on maintenance and mileage.

Reliability by variant

As a rule, reliability varies with how hard a model was driven and how well it was cared for. Here is a general snapshot by variant:

• Base V6: Typically the most durable and least costly to maintain, these cars tend to accumulate wear primarily in mechanical and suspension components as they age.


• GT (V8): Robust powertrain and drivetrain; many owners report solid reliability when oil and cooling maintenance are kept up, but costs rise with higher-mileage V8s and performance wear.


• Mach 1: A higher-performance variant that can handle routine driving well but may show more wear on exhaust, cooling and driveline components if it was driven aggressively.


• Cobra (SVT Terminator, if applicable to the market): The highest-performance end of the era; generally capable of strong reliability when professionally maintained, but maintenance costs and the potential for more demanding service needs are higher due to forced induction and upgraded hardware.

In practice, well-kept examples across these variants tend to be reliable for daily use, with the caveat that high-mileage cars and those with a history of hard driving require more careful inspection and ongoing maintenance.

Notes on model-year specifics

Because the Cobra and Mach 1 are limited-production variants with higher-performance hardware, they often attract owners who push the car harder. That can translate to greater wear on drivetrain and cooling components if the car wasn’t maintained with performance usage in mind. Always review maintenance history and inspect high-wear parts when evaluating these versions.

Common issues and recalls

Older Mustangs from this era share several categories of typical wear and failure, and some cars may have open safety or service campaigns. The following issues are commonly reported by owners and reviewers, though individual results vary based on history and care:

• Rust and corrosion in vulnerable areas (rocker panels, wheel arches, floor pans) in regions with road salt or past water intrusion.


• Electrical gremlins and aging connectors affecting interior electronics, lights, and instrument clusters.


• Oil, coolant, or transmission fluid leaks around seals and gaskets as gaskets age.


• Suspension wear on bushings and ball joints leading to creaks, clunks, or misalignment if not addressed.


• A/C/heater system aging components, including condenser, compressor, or blends doors causing reduced cooling/heating performance.

Recall history varies by vehicle and region; buyers should check the Ford recall database and verify that any open campaigns have been resolved or addressed by a dealer prior to purchase.

Costs, reliability scores and ownership expectations

As a mid-2000s performance car, the 2004 Mustang sits in the “affordable classic” space for maintenance and parts. Availability of aftermarket parts is strong, which helps keep repair costs reasonable relative to the age of the vehicle. Reliability scores from consumer-oriented outlets tend to place these cars in the average range for their era, with better scores if the car has a documented maintenance history and lower mileage.

Ownership costs include routine maintenance (oil changes, brake service, tires) and occasional major services (cooling system, transmission service, or brake hardware) that can be more frequent for performance variants. Insurance costs can also be higher for higher-performance versions depending on driver history and location.

How to evaluate a used 2004 Mustang

When assessing a car from this era, a systematic inspection and complete records are essential. Use this checklist to guide a pre-purchase evaluation:

1. Obtain a full maintenance and service history, including any accidents or major repairs.


2. Inspect for rust signs under the doors, wheel wells, frame rails, and trunk area.


3. Check the condition of the engine bay for oil leaks, coolant leaks, and worn hoses; listen for abnormal engine noises on startup and idle.


4. Test drive to evaluate transmission behavior, clutch operation (manual), throttle response, and any unusual shifting or slipping (automatic or manual).


5. Inspect the exhaust system, suspension, and steering components for wear or leaks; assess braking performance and pad/rotor condition.


6. Verify that all electrics function (windows, seats, HVAC, lights, gauges), and check for any dashboard warning lights.


7. Confirm that any open recalls have been addressed by a dealer and review recall status for the VIN.

A careful evaluation with a qualified mechanic who is familiar with older Ford modular engines can help identify hidden issues before purchase.

Maintenance tips to boost reliability

For owners hoping to maximize reliability and longevity, routine maintenance and proactive care are critical. The following practices are widely recommended by enthusiasts and independent technicians:

• Keep up with regular oil changes using quality synthetics appropriate for the engine, adhering to the mileage schedule.


• Replace timing chain guides and related components if the service history suggests wear (especially on higher-mileage engines) and monitor for any unusual engine timing noises.


• Serve cooling system proactively with coolant flushes and hose replacements to prevent overheating and radiator failures.


• Inspect and replace worn spark plugs, ignition coils (where applicable), and ignition wires to maintain smooth idle and power delivery.


• Service the transmission fluid (automatic) or assess the clutch and hydraulics (manual) to avoid abrupt shifts or slipping as mileage increases.


• Address rust quickly, treat affected areas, and consider undercoating or rust-proofing in harsher climates.


• Regularly inspect brakes, tires, and suspension components; replace worn bushings, ball joints, and control arms as needed.

Maintaining these elements can improve reliability and reduce costly surprises as these cars age.

Bottom line and summary

For a 2004 Mustang, reliability hinges on how well the car was maintained and how it has been driven. With solid maintenance, base V6 and GT models can offer dependable daily driving, while Mach 1 and Cobra variants reward careful owners with strong performance if kept up but can demand more costly maintenance. Overall, expect an average reliability profile for a 20-year-old performance coupe, with real-world costs reflecting parts availability and labor for an aging American classic.

In short, a well-cared-for 2004 Mustang can be a reliable choice for enthusiasts and daily drivers alike, provided you do due diligence, budget for maintenance, and understand the specific needs of the variant you choose.

Summary: The 2004 Mustang offers a broadly reasonable reliability outlook for a late-model classic, with the best prospects from well-documented, low-mileage vehicles and careful maintenance. Prospective buyers should prioritize maintenance history, inspect for rust and electrical faults, and be prepared for modest ongoing costs typical of an aging performance car.

How long do 2004 Mustangs last?

A 2004 Ford Mustang can last anywhere from 200,000 to over 300,000 miles, depending heavily on its maintenance history and how it was driven. With proper, consistent maintenance, these cars are known to be reliable and can reach high mileage, though specific models like the 4.6L V8 engine are particularly durable. 

• Typical lifespan: Many 2004 Mustangs can reach 200,000 miles or more with regular maintenance. 
• High-mileage potential: Meticulously maintained vehicles can reach 250,000 to 300,000 miles, and some have even exceeded 400,000 miles. 
• Influence of maintenance: Neglecting maintenance can significantly shorten a car's lifespan, while a history of diligent care is the key to longevity. 
• Engine reliability: The 4.6L V8 engine, found in models like the GT, is considered a tough and reliable motor that can last for many miles. The 4.0L V6 engine is also known for being reliable. 
• Other factors: A car's age can be a factor, as can the environment it was driven in. The body and interior may show wear and tear before the mechanicals fail, especially with good upkeep. 

Is the 2004 Ford Mustang reliable?

Among the 2048 owners who provided feedback on the 2004 Ford Mustang for Kelley Blue Book, consumer sentiment is overwhelmingly positive, with 93% recommending the vehicle. As a whole, consumers found the vehicle's performance and reliability to be its strongest features and comfort to be its weakest.

How much is a 2004 Mustang worth?

The price for a 2004 Ford Mustang varies significantly, with current used prices typically ranging from around $5,000 to $15,000 depending on the model and condition, while some high-end or low-mileage examples can go for much more. Original MSRPs for the 2004 model year ranged from approximately $18,150 to over $39,000, depending on the trim. 
Used car prices

• Typical range: Many used 2004 Mustangs are found in the $5,000 to $15,000 range, with prices heavily influenced by mileage, condition, and trim level. 
• Lower end: You can find very basic models or those with high mileage for as low as $500, say some eBay listings. 
• Higher end: Some performance-oriented models, like the SVT Cobra, or low-mileage examples, can fetch significantly higher prices. 
• Example listings: A 2004 Mustang GT Convertible might be listed around $15,000, while a low-mileage one-owner car could be listed for around $9,300. 

Original manufacturer's suggested retail prices (MSRP)

• V6 Standard Coupe: Around $18,150.
• GT Premium Convertible: Around $26,010.
• SVT Cobra Convertible: Around $39,240.
• Most expensive: The 2dr Conv SVT Cobra had the highest original MSRP at $39,240.
• Most affordable: The 2dr Cpe Standard had the lowest original MSRP at $18,150. 

What year to stay away from Mustang?

Years to avoid for the Ford Mustang include the 2015-2017 and 2019-2020 models, which have been associated with issues like transmission problems, electrical glitches, and warning light malfunctions. Older models to avoid include the 2005-2010 and 1999-2001 model years for various engine and design-related problems, as well as the entire Mustang II generation (1974-1978) due to poor performance. 
This video explains the issues with the 2015-2023 Ford Mustang S550 and provides a buyer's guide: 59sDiscerning CarsYouTube · Jan 15, 2024
Model years to avoid

• 2015-2017: Debut year of the sixth generation had numerous complaints, particularly for transmission, body panel, and electrical issues. The 2016 model year is noted for potential engine oil loss and air conditioning problems. 
• 2019-2020: Reported issues with cabin warning lights, including blind spot and forward collision warnings. 
• 2011-2012: Some 2011 models had issues after receiving the new "Coyote" 5.0L V8, and the 2012 model year saw further engine problems with the 3.7L V6. 
• 2005-2010: A long-running generation that has been cited for reliability issues. 
• 1999-2001: The 1999 facelift brought new issues, and the 2001 model also faced reliability concerns. 
• 1974-1978 (Mustang II): This entire generation is often considered one of the least reliable due to its poor performance and styling compared to other Mustang eras. 

General transmission issues

• 2011-2019: These years are frequently cited for problems with the MT82/MT82-D4 manual transmission, which can experience harsh shifting and other issues. 

Other notable years

• 1994-1995: These model years are on some "worst of" lists for specific problems. 
• 1996: The 1996 GT is sometimes criticized for a "dull" driving experience due to its new "mod" motor.