1. Product Overview
This manual provides essential information for the safe and correct installation, adjustment, and maintenance of your maXpeedingrods Coilover Suspension Kit. This kit is designed to enhance vehicle handling and allow for ride height adjustment.
Compatibility:
- Nissan 350Z Coupe/Roadster Convertible RWD (Z33) 2003-2008
- Infiniti G35 Coupe RWD (V35) 2003-2007
- Infiniti G35 Sedan RWD (V35) 2003-2006
- Nissan Skyline Coupe RWD (V35) 2003-2007
Note: Not compatible with AWD models.
2. Safety Information
Automotive suspension work requires specialized tools and knowledge. Improper installation can lead to serious injury or vehicle damage. It is highly recommended that installation be performed by a qualified professional technician.
- Always wear appropriate personal protective equipment (PPE), including safety glasses and gloves.
- Ensure the vehicle is securely supported on jack stands on a level surface before beginning any work. Never rely solely on a jack.
- Refer to your vehicle's factory service manual for specific torque specifications and removal/installation procedures for OEM components.
- Do not modify any components of the coilover kit.
- After installation, perform a full alignment of the vehicle.
3. Package Contents
Verify that all components are present and undamaged before beginning installation. Contact customer support immediately if any parts are missing or damaged.
- 4 x maXpeedingrods Coilover Assemblies (Front and Rear)
- Adjustment Wrenches (for ride height and preload)
- Instruction Manual (this document)
Figure 3.1: Detailed view of a coilover assembly, highlighting components such as the pillow ball top mount, dust boot, coil springs, 6061-T6 AL perch, anodized shock body, and powder-coated lower mount.
4. Setup and Installation
This section provides general guidelines. Always consult your vehicle's specific service manual for detailed removal and installation procedures of the original suspension components.
- Preparation: Park the vehicle on a level surface, engage the parking brake, and loosen the lug nuts on the wheels. Jack up the vehicle and secure it with jack stands. Remove the wheels.
- Remove OEM Suspension: Carefully remove the original shock absorbers and springs according to your vehicle's service manual. This typically involves disconnecting sway bar links, brake lines (if necessary), and unbolting the top mount and lower mount.
- Install New Coilovers:
- Install the new maXpeedingrods coilover assemblies. Ensure the top mount bolts align correctly with the vehicle's chassis mounting points.
- Attach the lower mount to the vehicle's control arm or knuckle.
- Reconnect any disconnected components (sway bar links, brake lines, etc.). Ensure all bolts are tightened to the manufacturer's specified torque.
- Initial Ride Height Setting: Before fully tightening all bolts, set an approximate ride height. Refer to the 'Operating and Adjustment' section for details on adjusting ride height.
- Final Assembly: Reinstall the wheels and lower the vehicle. Torque the lug nuts to specification.
- Post-Installation: Drive the vehicle for a short distance to allow the suspension to settle. Re-check all fasteners for tightness. A professional wheel alignment is mandatory after coilover installation.
Figure 4.1: Example of coilover installation. Professional installation is recommended.
5. Operating and Adjustment
Your maXpeedingrods coilovers allow for ride height adjustment. The damping value is preset for consistent performance.
5.1 Ride Height Adjustment
The ride height can be adjusted by twisting the lower mount on the threaded shock body. This allows for a lowering range of 1-3 inches from the original ride height.
- Loosen the lower mount (A) and locking ring (B) using the provided adjustment wrenches.
- Rotate the lower mount (A) to increase or decrease the threaded distance, thereby changing the ride height. Rotating clockwise will lower the vehicle, and counter-clockwise will raise it.
- Once the desired height is achieved, tighten the lower mount (A) and locking ring (B) securely against each other to prevent movement.
- Repeat for all four coilovers, ensuring even height on both sides of the vehicle.
Figure 5.1: Ride height adjustment mechanism showing the lower mount and locking rings.
5.2 Preload Adjustment
The preload on the spring can be adjusted using the locking ring (C) above the spring perch. This adjustment should only be performed by experienced individuals or professionals, as incorrect preload can affect ride quality and handling. The factory preset is generally suitable for most applications.
Figure 5.2: Visual representation of independent ride height and spring tension settings.
6. Maintenance
Regular maintenance ensures the longevity and optimal performance of your coilovers.
- Regular Inspection: Periodically inspect all coilover components for signs of wear, damage, or corrosion. Check for leaks around the shock body.
- Cleanliness: Keep the coilover threads and shock bodies clean from dirt, salt, and debris. A full-length dust boot is provided to protect the piston shafts.
- Fastener Checks: Regularly check the tightness of all mounting bolts, locking rings, and top mount nuts. Re-torque to specifications if necessary.
- Alignment: After any significant ride height adjustment, or if uneven tire wear is observed, have a professional wheel alignment performed.
7. Troubleshooting
This section addresses common issues that may arise with coilover suspension.
| Symptom | Possible Cause | Solution |
|---|---|---|
| Unusual noises (clunking, squeaking) | Loose fasteners, worn bushings, improper installation. | Inspect all mounting points and tighten to specifications. Check for damaged bushings. Re-evaluate installation. |
| Uneven ride height | Incorrect height adjustment, uneven preload. | Re-measure and adjust ride height on all four corners. Ensure preload is consistent. |
| Poor handling or ride quality | Incorrect ride height, improper alignment, damaged components. | Verify ride height settings. Perform a wheel alignment. Inspect coilovers for damage. |
| Shock absorber leaking | Seal failure, damage to shock body. | Contact customer support for warranty or replacement options. |
8. Specifications
| Feature | Specification |
|---|---|
| Model Number | YH41DW |
| Front Spring Rate | 10 kg/mm (560 lbs/in) |
| Rear Spring Rate | 7 kg/mm (392 lbs/in) |
| Ride Height Adjustment | 1-3 inches lowering (from original ride height) |
| Damping | Preset |
| Top Mount Material | 6061-T6 Aluminum Alloy (Pillow Ball) |
| Spring Material | 55CrSi Steel (Cold-Bent) |
| Shock Body Finish | Anodized with Anti-Corrosion Coating |
| Lower Mount Finish | Powder-Coated |
| Item Weight | 26650 Grams (Total for kit) |
Figure 8.1: Dimension details for front and rear coilover units, including spring rates.
9. Warranty Information
maXpeedingrods products are manufactured to high standards. For specific warranty terms and conditions, please refer to the official maXpeedingrods website or contact their customer service directly. Keep your proof of purchase for any warranty claims.
10. Support
If you encounter any issues or have questions regarding the installation, adjustment, or performance of your maXpeedingrods Coilovers, please contact maXpeedingrods customer support. Provide your product model number (YH41DW) and purchase details for efficient assistance.
Contact Information:
- Visit the official maXpeedingrods website for support resources and contact options.
- Refer to your purchase platform for seller-specific support channels.