2004 Dodge Durango Rear Coil Springs: Solving Sag, Lean, and Matching Spring Codes

Understanding Your 2004 Durango's Suspension

The 2004 Dodge Durango, the first year of the second generation, has a unique suspension setup. The front uses torsion bars, while the rear suspension features a solid axle supported by coil springs and shock absorbers. This article focuses exclusively on the rear coil springs, as there are no factory-installed coil springs in the front suspension.

These rear springs are crucial for ride quality, load-carrying capacity, and overall stability. Over time, these springs can wear out, leading to a number of noticeable problems.

Common Symptoms of Failing Rear Coil Springs

When your original coil springs begin to fail, you'll likely notice one or more of the following symptoms:

• Vehicle Sagging: The most common symptom is a visibly lower rear ride height, especially when compared to the front. The vehicle may look like it's squatting, even with no cargo.
• Leaning to One Side: If one spring fails or weakens more than the other, the Durango will lean or sag on one corner.
• Bottoming Out: Weak springs can't properly absorb impacts, causing the suspension to hit its bump stops over bumps or dips in the road. This results in a harsh jolt and loud thud.
• Excessive Bouncing: After hitting a bump, the rear of the vehicle may continue to bounce instead of settling down quickly.
• Clunking or Creaking Noises: A broken or unseated spring can make metallic clunking or popping sounds as the suspension moves.
• Poor Handling and Swaying: Worn springs can cause the vehicle to feel unstable and sway excessively, especially when turning or carrying a load.

Known Issues, TSBs, and Recalls

As of this writing, there are no specific recalls or widespread Technical Service Bulletins (TSBs) from Dodge directly related to the failure of the rear coil springs on the 2004 Durango. Most issues are related to normal wear and tear over time. However, several recalls were issued for other suspension and axle components:

• NHTSA Recall 04V-578: A recall was issued for the positive battery cable potentially rubbing against a front suspension bracket, which could cause a fire. This does not directly involve the springs but is a critical safety check for any owner.
• Front Upper Ball Joints: A major recall was issued for 2000-2003 models for failing upper ball joints. While this doesn't cover the 2004 model year, it highlights a point of attention for the front suspension.
• Suspension TSBs: A TSB (#0200104) was issued for a "squawk" noise from the stabilizer bar bushings, which can be mistaken for a spring noise. Other TSBs relate to axle fluid levels and contamination.

Buyer's Guide: What to Check Before Purchasing Used 2004 Durango Coil Springs

Buying a used OEM coil spring is an excellent way to save money and get a part with the correct specifications. However, a careful inspection is critical.

The Most Important Step: Match the Spring Code

Dodge used several different rear coil springs for the 2004 Durango to account for different vehicle weights and options like the trailer tow package. To ensure you get the correct ride height and load capacity, you must match the 3-letter code printed on a tag on your original spring. Examples of these codes include 'ZAR', 'ZNR', 'ZAS', and 'ZNS'. Installing springs with the wrong code can result in an uneven ride height or poor performance when towing.

Physical Inspection Checklist

• Check for Cracks: Carefully inspect the entire spring, especially the top and bottom coils where they sit in the mounts. Any crack, no matter how small, means the spring is unsafe and should be rejected.
• Inspect for Heavy Rust and Pitting: Surface rust is normal, but deep, flaky rust or pitting weakens the steel and can lead to premature failure.
• Look for Deformation: The spring should be straight and uniform. Any signs of bending, twisting, or collapsed coils indicate it has been overloaded or damaged.
• Measure the Free Height: If possible, compare the uninstalled height of the used spring to your other spring or its specifications. A significant difference in height indicates it has sagged and lost its strength.
• Get the Pair: Always buy and replace coil springs in pairs for the same axle to ensure an even ride height and balanced handling.

Rear Coil Spring Replacement Overview

Replacing the rear coil springs on a 2004 Durango is a straightforward job for a DIY mechanic with the right tools. Because of the solid axle design, spring compressors are typically not required.

• Installation Difficulty: 2 out of 5
• Estimated Time: 1.5 - 2.5 hours
• Tools Needed: Jack stands, floor jack, socket set (15mm, 18mm), breaker bar, wrenches.

Simplified Step-by-Step Guide

1. Safely lift the rear of the vehicle by the frame and support it with jack stands, allowing the rear axle to hang freely. Chock the front wheels.
2. Place a floor jack under the rear differential to support its weight.
3. Remove the rear wheels.
4. Disconnect the bottom mounts of the rear shock absorbers (15mm and 18mm bolts/nuts).
5. Disconnect the rear sway bar end links from the axle.
6. Slowly lower the floor jack supporting the rear axle. The axle will droop down, relieving all tension on the coil springs.
7. Once the axle is low enough, the old coil springs and their rubber isolators can be pulled out by hand.
8. Install the new springs, making sure they are correctly seated in the upper and lower mounts with their isolators.
9. Raise the axle with the floor jack, guiding the springs into position. Reconnect the shock absorbers and sway bar links.
10. Reinstall the wheels, lower the vehicle, and torque all fasteners to specification.

Cost Comparison: 2004 Durango Rear Coil Springs

Frequently Asked Questions (FAQ)