2004 Chevrolet Trailblazer EXT

2004 Chevrolet Trailblazer EXT

Overview

The 2004 Chevrolet Trailblazer EXT, a full-size SUV known for its extended wheelbase offering increased cargo and passenger space, presented a mixed bag of reliability. While generally considered a capable vehicle for its class, certain model years and specific components experienced more frequent issues than others. Owners often reported concerns related to the powertrain, particularly with specific engine and transmission configurations. The electrical system and some interior components also showed a propensity for problems. However, the overall structure and exterior held up reasonably well for many users, with the primary focus of reliability concerns centering on mechanical and electrical systems that could lead to significant repair costs and downtime.

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Engine

4.2L Vortec Inline-6

Intake Manifold Gasket Leaks

• Symptoms: Coolant leaks, overheating, rough idle, potential misfires.
• Solution: Replacement of the intake manifold gasket.
• Cost: $300 - $600

Oil Cooler Lines Leaking

• Symptoms: Visible oil leaks, low oil pressure, potential engine damage if not addressed.
• Solution: Replacement of leaking oil cooler lines.
• Cost: $400 - $700

5.3L Vortec V8

Active Fuel Management (AFM) Issues

• Symptoms: Engine misfires, rough idle, increased oil consumption, potential lifter failure.
• Solution: Deactivation of AFM system or repair/replacement of lifters and related components.
• Cost: $1,500 - $3,000+

Intake Manifold Gasket Leaks

• Symptoms: Coolant leaks, overheating, rough idle, potential misfires.
• Solution: Replacement of the intake manifold gasket.
• Cost: $300 - $600

Transmission

4L60-E 4-Speed Automatic

Torque Converter Failure

• Symptoms: Slipping gears, shuddering, difficulty shifting, potential loss of drive.
• Solution: Rebuild or replacement of the torque converter and potentially the transmission.
• Cost: $1,200 - $2,500

Overheating

• Symptoms: Delayed shifting, harsh shifts, burning smell, transmission fluid leaks.
• Solution: Installation of an auxiliary transmission cooler, fluid flush, and inspection for internal damage.
• Cost: $300 - $700

Suspension

Standard Chassis

Front Wheel Bearing Failure

• Symptoms: Grinding noise from front wheels, humming noise that increases with speed, looseness in steering.
• Solution: Replacement of the front wheel bearing assembly.
• Cost: $300 - $550

Ball Joint Wear

• Symptoms: Clunking noises over bumps, uneven tire wear, steering instability.
• Solution: Replacement of worn ball joints.
• Cost: $400 - $700

Electrical

Body Control Module (BCM)

Intermittent Electrical Failures

• Symptoms: Power windows not working, interior lights flickering, door locks malfunctioning, dashboard warning lights illuminating randomly.
• Solution: Diagnosis and potential reprogramming or replacement of the BCM.
• Cost: $500 - $1,000

Alternator

Premature Failure

• Symptoms: Battery warning light illuminated, dimming headlights, electrical system malfunctions, dead battery.
• Solution: Replacement of the alternator.
• Cost: $400 - $700

Exterior

Standard Body

No Major Issues

• Symptoms: No widespread issues reported.
• Solution: No widespread issues reported.
• Cost: No widespread issues reported.

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.
• Cost: $200 - $400

Seat Actuators

Power Seat Malfunctions

• Symptoms: Power seats not moving forward/backward or up/down.
• Solution: Repair or replacement of the seat motor or switch.
• Cost: $300 - $600

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Summary Verdict

The 2004 Chevrolet Trailblazer EXT, particularly with the V8 engine option, can be prone to powertrain issues such as torque converter failure and Active Fuel Management problems, which can be costly to repair. The electrical system, especially the Body Control Module, also presents a risk for intermittent and frustrating malfunctions. While the suspension components like wheel bearings and ball joints can wear out, these are somewhat expected for a vehicle of its age and size. The exterior generally holds up well, but interior components like HVAC actuators and power seat motors can fail. Prospective buyers should be aware of these potential issues and factor in possible repair costs when considering this model.