Monroe 58630 Load Adjusting Suspension Shock Absorber and Coil Spring Assembly Instruction Manual

1. Introduction and Overview

This manual provides essential information for the proper installation, operation, and maintenance of your Monroe 58630 Load Adjusting Suspension Shock Absorber and Coil Spring Assembly. These shock absorbers are engineered to enhance vehicle control and stability, particularly when carrying or towing varying loads.

Image 1.1: Two Monroe 58630 Load Adjusting Shock Absorbers. These units feature an integrated coil spring designed to support additional weight.

2. Compatibility

The Monroe 58630 Load Adjusting Suspension Shock Absorber and Coil Spring Assembly is compatible with the following vehicle models:

• Dodge Dakota: 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
• Dodge Durango: 1999, 2000, 2001, 2002, 2003

Always verify compatibility with your specific vehicle's year, make, model, engine, and trim before installation. Consult your vehicle's owner's manual for additional information.

3. Product Features

• Reduces Sag Under Load: Features a heavy-gauge, calibrated coil spring that reduces vehicle sag when loaded up to 1,200 lbs. (Note: Capacity is limited by vehicle suspension, tires, and transmission; refer to your vehicle's owner's manual).
• Exceptional Handling: Tuned specifically for each application, full-displaced valving automatically adjusts to road extremes, providing consistent ride quality.
• Consistent Ride: OE all-weather fluid contains special modifiers to handle extreme temperatures. A PTFE-banded piston reduces friction between the piston and pressure tube, enhancing responsiveness to changing road surfaces.
• Longer Service Life: A self-lubricating fluid seal retains gas and reduces excessive friction against the piston rod, helping to prevent premature wear. The heavy-duty nitrocarburized rod contributes to long product life.
• Improves Performance: Nitrogen gas-charge maintains tire-to-road contact for improved ride and handling by reducing aeration and shock fade.

Image 3.1: Illustration of the Monroe shock absorber highlighting its load-adjusting capability. The integrated coil spring helps maintain vehicle height under varying loads.

4. What's in the Box

Each package of Monroe 58630 Load Adjusting Suspension Shock Absorbers typically includes:

• Two (2) Monroe 58630 Load Adjusting Shock Absorbers
• Dust Shield(s)
• Parts Pack(s) (containing necessary hardware for installation)

5. Setup and Installation

Installation of suspension components requires mechanical knowledge and appropriate tools. If you are not confident in your ability to perform this installation, it is recommended to seek professional assistance.

5.1. Safety Precautions

• Always wear appropriate personal protective equipment, including safety glasses and gloves.
• Ensure the vehicle is on a stable, level surface and properly supported with jack stands before beginning work.
• Never work under a vehicle supported only by a jack.
• Refer to your vehicle's service manual for specific torque specifications and procedures.

5.2. General Installation Steps (Rear Shocks)

1. Prepare Vehicle: Park the vehicle on a level surface, engage the parking brake, and block the front wheels. Loosen the rear wheel lug nuts.
2. Lift Vehicle: Safely lift the rear of the vehicle using a floor jack and support the frame with jack stands, allowing the rear axle to hang freely. This is crucial as the new shocks come fully extended.
3. Remove Wheels: Remove the rear wheels.
4. Remove Old Shocks: Locate the upper and lower mounting bolts of the existing shock absorbers. Carefully remove these bolts. You may need to use a second jack (e.g., a bottle jack) under the axle to slightly adjust its height to relieve tension on the bolts.
5. Inspect Mounting Points: Clean and inspect the mounting points for any damage or wear.
6. Install New Shocks:
   • Position the new Monroe 58630 shock absorber. You may need to use a jack under the axle to compress the shock slightly or adjust the axle height to align the mounting holes.
   • Install the upper mounting bolt first, then the lower. Do not fully tighten bolts until the vehicle is at ride height.
   • Ensure the dust shield and any other components from the parts pack are installed correctly.
   • Note: For some Dodge Dakota models, it may be necessary to relocate the passenger side brake line to prevent rubbing on the coil spring. Inspect carefully after installation.
7. Lower Vehicle: Reinstall the wheels and hand-tighten lug nuts. Carefully lower the vehicle until it is resting on its own weight.
8. Final Tightening: With the vehicle at ride height, fully tighten all shock mounting bolts to the manufacturer's specified torque. Then, fully tighten the lug nuts.
9. Test Drive: Perform a short test drive to ensure proper operation and check for any unusual noises or handling characteristics.

Image 5.1: A mechanic measuring vehicle ride height. Proper measurement before and after installation can help confirm correct setup.

Image 5.2: A vehicle raised on a lift, showing a mechanic inspecting the suspension area. This illustrates the environment for shock absorber installation.

6. Operating Principles

The Monroe 58630 Load Adjusting Shock Absorber is designed to provide variable support based on the load applied to the vehicle. Unlike standard shock absorbers, these units incorporate a heavy-gauge coil spring around the shock body. This coil spring works in conjunction with the shock's damping system to:

• Maintain Ride Height: The coil spring provides additional support to the vehicle's rear suspension, helping to prevent excessive sag when carrying heavy loads or towing.
• Improve Stability: By reducing sag, the shocks help maintain proper vehicle geometry, which contributes to better steering response and overall stability, especially during cornering or braking with a load.
• Enhance Ride Comfort: The shock's internal valving adjusts to road conditions, working with the coil spring to absorb impacts and control suspension movement, leading to a more consistent and comfortable ride whether loaded or unloaded.

The nitrogen gas charge within the shock helps to prevent fluid aeration, ensuring consistent damping performance even under demanding conditions.

7. Maintenance

Monroe 58630 Load Adjusting Shock Absorbers are designed for long-term, maintenance-free operation. However, regular inspection of your vehicle's suspension components is recommended as part of routine vehicle maintenance.

• Visual Inspection: Periodically check the shock absorbers for signs of fluid leaks, bent rods, damaged bushings, or corrosion.
• Mounting Hardware: Ensure all mounting bolts are secure and properly torqued.
• Tire Wear: Uneven tire wear can sometimes indicate suspension issues. If observed, have your suspension system inspected.
• Performance Check: If you notice a decrease in ride comfort, increased body roll, or excessive bouncing, it may be time to inspect or replace your shock absorbers.

Always consult your vehicle's owner's manual for recommended service intervals and procedures.

8. Troubleshooting

If you experience issues after installing your Monroe 58630 shock absorbers, consider the following common troubleshooting steps:

• Excessive Bouncing or Poor Ride Quality:
  • Verify that the correct shock absorbers were installed for your vehicle model.
  • Check all mounting hardware for proper tightness. Loose bolts can affect performance.
  • Inspect for any signs of damage or fluid leaks on the shock body.
• Unusual Noises (e.g., clunking, squeaking):
  • Ensure all mounting bolts are securely fastened and bushings are properly seated.
  • Check for any contact between the shock absorber or coil spring and other vehicle components (e.g., brake lines, frame).
  • Inspect for damaged or worn bushings.
• Vehicle Sagging or Uneven Ride Height:
  • Confirm that the shocks are fully extended when the vehicle is lifted and that the coil springs are intact.
  • Ensure the vehicle is not overloaded beyond its specified capacity (including the 1,200 lbs. capacity of the shocks, which is limited by other vehicle components).
  • Check for other worn suspension components (e.g., leaf springs, control arm bushings) that might be contributing to sag.

If troubleshooting steps do not resolve the issue, contact Monroe customer support or a certified automotive technician.

9. Specifications

10. Warranty and Support

For information regarding product warranty, technical support, or any other inquiries, please refer to the official Monroe Shocks & Struts website or contact their customer service department directly. Keep your purchase receipt as proof of purchase for warranty claims.

Monroe Official Website: www.monroe.com