Gabriel 85958 Fleetline Heavy Duty Front Shock Absorbers Instruction Manual

1. Introduction

This manual provides essential information for the installation, operation, and maintenance of the Gabriel 85958 Fleetline Heavy Duty Front Shock Absorbers. These shock absorbers are designed for heavy-duty commercial vehicles, offering ride control solutions for demanding applications. Please read this manual thoroughly before proceeding with any procedures.

2. Product Overview and Features

The Gabriel Fleetline 85958 shock absorbers are engineered for heavy-duty commercial vehicles and fleet operations. They are designed as direct replacements for original equipment shocks, providing a valving rate that compensates for initial suspension softening to match original ride performance.

Image 2.1: Gabriel 85958 Fleetline Heavy Duty Front Shock Absorber with packaging.

Key Features:

• Bore Size: Larger 1 5/8-inch bore for improved durability and tensile strength in harsh operating conditions.
• Piston Rod: Chromed piston rod to inhibit corrosion, ensure proper seal lubrication, and provide a consistent wear surface.
• End Mounts: Solid steel eye rings and 360-degree arc-welded end mounts deliver tensile strength, reducing end mount failures. Anti-corrosion treatment inhibits rust.
• Piston Seal: Durable, self-compensating piston seal design reduces force-velocity variabilities and extends product life.
• Valving: 10-stage valving ensures consistent performance and compensates for suspension wear.
• Fluid Capacity: Bulged design (on 85300 & 85700 series, check specific model for applicability) provides increased fluid capacity for cooler operation.
• Shock Oil: Formulated shock oil for anti-fade performance.
• Hydraulic Rebound Stop: Prevents shocks from topping out and suspensions from overextending (where applicable).

Image 2.2: Internal components of the Gabriel Fleetline shock absorber, highlighting features like the chromed piston rod, multi-lip piston rod seal, bulged design, and self-compensating piston seal.

3. Specifications

Detailed specifications for the Gabriel 85958 Fleetline Heavy Duty Front Shock Absorber are provided below:

Image 3.1: Detailed dimensional and performance specifications for the 85958 Fleetline Shock.

4. Vehicle Fitment

The Gabriel 85958 Fleetline Heavy Duty Front Shock Absorbers are compatible with a range of heavy-duty commercial vehicles. Verify compatibility with your specific vehicle model and year before installation.

Applications include:

• Dynamax Corp: Dynaquest XL (09-24), Grand Sport GT (09-14), Grand Sport Ultra (09-14), GT Toy Hauler (09-13).
• Freightliner: 114SD (12-24), 122SD (13-23), Cascadia (09-20), Columbia (09-20), Coronado (10-20), FLD120 (09-11), FLD132 (09-11), FLD120SD (09-12), M2 112 (09-24).
• Pierce Mfg. Inc.: Various Models with Freightliner Chassis (M2 112 or 114SD with 12000 lb to 20000 lb Front Axle), Front, FIRE - RESCUE (13-11).
• Renegade: Various Models with Freightliner M2-112 Chassis with 12000 lb to 20000 Front Axle, Front, TRUCK & TRACTOR - CLASS 7 / 8 (11-10); Various Ikon Series Motorhomes with Freightliner Cascadia Chassis and 12,000 to 13,300 lb Taperleaf Front Suspension, Front, MOTORHOME (14-13); Various Renegade XL Series Motorhomes with Freightliner Cascadia Chassis and 12,000 to 13,300 lb Taperleaf Front Suspension, Front, MOTORHOME (17-16).
• Western Star: 4700SB (12-20), 4800SB (12-20), 4800SF (13-20), 4900EX (08-20), 4900FA (08-20), 4900SA (08-20), 5700XE (16-22), 6900XD (09-19).

5. Installation

Installation of shock absorbers should be performed by a qualified technician using appropriate safety equipment and following vehicle manufacturer guidelines. Incorrect installation can lead to vehicle damage or personal injury.

General Installation Considerations:

• Ensure the vehicle is safely supported on a lift or jack stands.
• Remove the old shock absorber according to the vehicle service manual.
• Inspect mounting points for wear or damage and replace components as necessary.
• Install the new Gabriel 85958 shock absorber, ensuring all bolts and nuts are tightened to the manufacturer's specified torque.
• The shock is tuned with application-specific valving to compensate for worn suspension.
• Features like the self-compensating piston seal, 360-degree arc-welded end mounts, and chromed piston rods contribute to durability and corrosion resistance.

Refer to your vehicle's specific service manual for detailed, step-by-step installation instructions.

6. Operation

Once installed, the Gabriel 85958 Fleetline Heavy Duty Front Shock Absorbers function automatically as part of your vehicle's suspension system. They are designed to:

• Dampen spring oscillations, providing a smoother ride.
• Maintain tire contact with the road surface for improved traction and control.
• Reduce vehicle body roll and sway during turns and braking.
• Contribute to overall vehicle stability and handling, especially under heavy loads or demanding conditions.

The application-specific valving ensures consistent performance even as other suspension components may experience wear.

7. Maintenance

Regular inspection of your shock absorbers is crucial for maintaining vehicle safety and performance. While Gabriel Fleetline shocks are built for durability, periodic checks can help identify potential issues early.

Recommended Maintenance Checks:

• Visual Inspection: Regularly check for signs of fluid leaks around the piston rod and seal area. A light film of oil is normal, but excessive wetness indicates a leak.
• Mounting Points: Inspect the upper and lower mounting points for looseness, wear, or damage to bushings and bolts.
• Physical Damage: Look for dents, bends, or other physical damage to the shock body or piston rod.
• Performance Check: Pay attention to changes in ride quality, excessive bouncing, or reduced vehicle control, which may indicate worn shocks.

If any issues are detected, it is recommended to have the shock absorbers inspected and replaced by a professional technician.

8. Troubleshooting

If you experience issues with your vehicle's suspension after installing Gabriel 85958 Fleetline shocks, consider the following common troubleshooting points:

Common Issues and Solutions:

• Excessive Bouncing or Sway: This often indicates worn or failing shock absorbers. If new shocks are installed and this persists, verify correct installation and ensure the shocks are the correct application for your vehicle.
• Fluid Leaks: A significant fluid leak from the shock body indicates a failed seal. The shock absorber will need to be replaced.
• Clunking or Rattling Noises: These sounds can be caused by loose mounting hardware, worn bushings, or internal shock damage. Inspect mounting points and bushings, and tighten fasteners to specification. If the noise persists, the shock may be faulty.
• Uneven Tire Wear: Worn shock absorbers can contribute to uneven tire wear patterns (e.g., cupping). While shocks are not the sole cause, they play a role in maintaining tire contact.
• Harsh Ride: If the ride feels unusually stiff, ensure the correct shock absorber model was installed and that no other suspension components are seized or damaged.

For persistent or complex issues, consult a professional automotive technician.

9. Warranty and Support

For information regarding the warranty coverage for your Gabriel 85958 Fleetline Heavy Duty Front Shock Absorbers, please refer to the official Gabriel website or contact Gabriel customer support directly. Warranty terms and conditions may vary.

For technical assistance, product inquiries, or to locate authorized service centers, visit the official Gabriel website or contact their customer service department.