How To Adjust Preload On Coilovers

How to Adjust Preload on Coilovers: A Comprehensive Guide

So, you've upgraded your car's suspension with coilovers, and now you're looking to fine-tune the ride. One crucial aspect of this is adjusting the preload. Understanding how to adjust preload correctly is key to achieving the optimal handling and comfort balance for your vehicle. This guide will walk you through the process, covering everything from understanding preload to the actual adjustment.

What is Preload?

Preload refers to the initial compression applied to your coilover springs before any weight is applied from the vehicle. It's essentially the amount of force the spring is already under before your car's weight settles on it. Think of it like pre-stretching a rubber band – it's already slightly taut before you use it.

Why is Preload Important?

Correct preload setting significantly impacts several aspects of your car's handling and ride:

• Ride Height: Preload directly influences your car's ride height. Too much preload can make your car sit too high, while too little can make it sit too low.
• Suspension Travel: Proper preload ensures that you have sufficient suspension travel (both up and down) for optimal comfort and to prevent bottoming out.
• Spring Rate: While not directly changing the spring rate, incorrect preload can affect how the spring rate feels. Improper settings may make the car feel stiff or unresponsive.
• Handling: This ties into the other aspects. An incorrectly set preload can affect the balance of the car, impacting steering response and stability.

Tools You'll Need

Before you begin, gather these essential tools:

• Correct size wrench or socket: This will depend on your specific coilovers, so check your manual.
• Jack and jack stands: Absolutely essential for safety. Never work under a car supported only by a jack.
• Wheel chocks: To prevent the car from rolling.
• Measuring tape or ruler: For accurate ride height measurements.
• Pen and paper or digital record-keeping: Keep track of adjustments you make.
• Owner's Manual (if available): This may contain specific instructions for your coilovers.

Step-by-Step Guide to Adjusting Coilovers Preload

Safety First! Always prioritize safety. Never work under a car without properly securing it with jack stands. Ensure the car is on a level surface.

1. Secure the Vehicle: Safely lift your car using a jack and secure it with jack stands. Engage the parking brake and use wheel chocks on the wheels that remain on the ground.

2. Locate the Preload Adjustment: This is usually a threaded collar or ring on the shock body. Consult your coilovers' instructions if unsure.

3. Measure Initial Ride Height: Measure the distance from a specific point on the chassis to the ground (e.g., the bottom of the fender). This establishes a baseline.

4. Adjust the Preload: Using the appropriate wrench, turn the preload adjustment collar. Clockwise rotation generally increases preload, raising the ride height, while counter-clockwise rotation decreases preload, lowering the ride height.

5. Make Small Adjustments: Make small adjustments (e.g., ¼ to ½ turn) at a time. Lower the car slightly to the ground (carefully!) after each adjustment to assess the ride height.

6. Re-measure Ride Height: After each adjustment, re-measure the ride height. This allows you to monitor the changes and avoid over-adjustment.

7. Repeat as Necessary: Continue adjusting until you achieve the desired ride height. Remember to maintain equal preload on both sides of the vehicle. Significant differences in preload can negatively impact handling.

8. Final Check: Once satisfied with the ride height, lower the car completely and check for proper suspension travel. Ensure there’s enough clearance to avoid bottoming out.

9. Test Drive: After making adjustments, take a test drive to evaluate the handling and comfort. Fine-tune as needed based on your experience.

Troubleshooting and Tips

• Uneven Ride Height: If you have uneven ride height after adjustments, check the suspension components for any damage or binding.
• Excessive Bouncing: This might indicate insufficient preload.
• Stiff Ride: This might indicate excessive preload.

Remember, finding the optimal preload setting is a process of adjustment and fine-tuning. Be patient, methodical, and prioritize safety. If you're unsure about any step, it's always best to consult a professional mechanic.