Getting your Truhart coilovers dialed in right is key to unlocking your car’s full handling potential. This guide will walk you through exactly how to adjust Truhart coilovers, from initial setup to fine-tuning your ride height and damping. Whether you’re aiming for a perfect stance or a track-ready setup, understanding these adjustments is essential.
Proper adjustment ensures you get the performance and look you paid for. Incorrect settings can lead to poor handling, a uncomfortable ride, or even damage. We’ll cover everything from the tools you’ll need to the step-by-step process, making sure you can do it safely and correctly.
How To Adjust Truhart Coilovers
Adjusting your coilovers involves three main areas: ride height, preload, and damping. Each one affects your car’s behavior differently. It’s important to adjust them in the correct order to avoid confusion and get the best results. We’ll break down each step clearly.
Tools and Safety Gear You’ll Need
Before you start, gather your tools. Having everything on hand will make the job smoother and safer. You don’t want to be under the car searching for a wrench.
- Jack and jack stands (NEVER rely on a jack alone)
- Lug wrench
- Socket set and wrenches
- Coilover spanner wrenches (usually included with Truhart kits)
- Measuring tape or ruler
- Penetrating oil (like WD-40) for stubborn parts
- Safety glasses and gloves
- A flat, level surface to work on
Understanding the Main Adjustment Points
Let’s quickly identify what you’ll be turning. Knowing the parts prevents mistakes.
- Ride Height Collar: This is the large, threaded ring the spring sits on. Turning it moves the entire shock body up or down in the mounting bracket, changing your car’s height without affecting spring tension.
- Preload (Spring Collar): This is a separate ring that compresses the spring. Its main job is to remove slack, not to stiffen the spring. Correct preload is crucial.
- Damping Adjuster: Usually a knob on the top of the shock (or bottom, on some rear setups). It controls how fast the shock compresses and rebounds, affecting ride comfort and grip.
Step 1: Setting Your Initial Ride Height
Always set ride height before touching preload or damping. This is the most impactful adjustment. The goal is to get your desired look and maintain suspension geometry.
- Securely lift the car and remove the wheels. Work on one corner at a time for consistency.
- Locate the ride height collar on the coilover body. It’s locked in place by a smaller lock ring.
- Use the spanner wrench to loosen the lock ring by turning it counter-clockwise.
- Now, turn the main ride height collar. Clockwise raises the car, counter-clockwise lowers it. Make small adjustments, like a quarter-turn at a time.
- After adjusting, tighten the lock ring firmly against the ride height collar to prevent it from moving.
- Lower the car, bounce the suspension a few times, then measure from the center of the wheel hub to the fender lip. This is a more consistent measurement than from the ground.
- Repeat for all four corners, aiming for your target measurements. It may take a few tries to get it even.
Step 2: Correctly Setting Spring Preload
Preload is often misunderstood. You don’t set it to make the spring stiffer. You set it to ensure the spring is properly seated at full droop. Too much preload can ruin ride quality.
- With the car still on the ground, check if there’s any gap between the spring coils when the suspension is at full droop (you may need to lift the control arm slightly to simulate this). There shouldn’t be.
- If there is a gap, you need to add preload. Lift the car so the wheel just hangs, supporting the control arm with a jack stand for safety.
- Loosen the lock ring on the spring perch collar.
- Turn the spring perch collar clockwise until all slack is removed from the spring. You should just feel the spring become snug—do not compress it further.
- Tighten the lock ring securely. The spring should not rotate freely by hand when correct.
A Note on Corner Weighting
For ultimate performance, especially on track, corner weighting is the next step. This uses special scales to balance the weight on each tire. It requires precise ride height tweaks and is best done by a professional if you’re not familiar with the process. For most street applications, even hub-to-fender measurements are sufficient.
Step 3: Adjusting Damping (Rebound)
Truhart coilovers typically feature adjustable rebound damping. This controls how quickly the shock extends after being compressed. Softer settings are more comfortable; firmer settings improve control.
- Start with the softest setting. Turn the damping knob fully counter-clockwise until it stops. This is usually the “soft” or “0” position.
- For a balanced street setup, try starting in the middle. Turn the knob clockwise, counting the clicks or turns until it stops (full stiff). Then, set it back to the halfway point.
- Test drive the car. Pay attention to how it feels over bumps, during cornering, and on highway transitions.
- If the car feels bouncy or floats, increase the damping (turn clockwise) a few clicks at a time.
- If the ride is too harsh and transmits every small bump, decrease the damping (turn counter-clockwise).
- Adjust front and rear separately. Often, a slightly stiffer front or rear can help with understeer or oversteer balance.
Fine-Tuning and Test Drive Protocol
Adjustment is an iterative process. You won’t get it perfect on the first try. Follow a logical test routine.
- Find a familiar road with a mix of surfaces: smooth asphalt, rough patches, and some corners.
- Make one change at a time. Only adjust damping OR height, not both, before a test drive.
- Listen for noises. Clunking after adjustment might mean something isn’t tight or preload is incorrect.
- Allow for settle time. New coilovers may settle a few millimeters over the first 50-100 miles. Re-check your height after a week of driving.
Common Mistakes to Avoid
Avoid these pitfalls to save time and prevent damage. They’re more common then you might think.
- Maxing Out Low: Lowering the car until the spring is fully compressed or the shock bottoms out. This destroys ride quality and can break components.
- Ignoring Preload: Leaving spring slack causes a horrible clunking noise on rebound and inconsistent handling.
- Forgetting to Tighten Lock Rings: This is the biggest cause of settings shifting during driving. Always double-check they are tight.
- Uneven Measurements: Not using a consistent measuring point leads to a crooked ride height and poor handling.
- Setting Damping Too Stiff: On bumpy roads, overly stiff shocks can make the tires lose contact, actually reducing grip.
Maintenance Tips for Longevity
Coilovers need a little care to last. Simple checks go a long way to preserving your investment.
- Periodically check all lock rings and mounting nuts for tightness, especially after the first 500 miles.
- Keep the damper shafts and threaded bodies clean. Dirt grinds away the seals and threads. A soft brush works well.
- If your coilovers have dust boots, make sure they are in place and not torn.
- Listen for new noises. Squeaks might just need lubrication on the spring perches, but knocking needs investigation.
Frequently Asked Questions (FAQ)
How do I adjust Truhart coilovers for a smooth ride?
Start with ride height that provides adequate suspension travel. Ensure preload is set correctly—just enough to remove slack. Then, set the damping to the softest or near-softest setting. Test and increase stiffness only if the car feels too bouncy.
What is the correct way to set preload on Truhart coilovers?
The correct way is to remove all free play from the spring when the suspension is at full droop. You should not be compressing the spring to make it stiffer. The springs rate determines stiffness; preload just ensures it stays seated.
Can I adjust the height on my Truhart coilovers myself?
Yes, adjusting the height is the most common DIY task. As long as you have the correct spanner wrenches, jack stands, and follow the steps to loosen the lock ring first, it’s a straightforward job. Always re-tighten the lock ring securely.
Why are my newly installed Truhart coilovers making a clunking noise?
A clunk is often caused by incorrect spring preload (too loose), a loose top mount nut, or a loose lock ring on the ride height collar. Double-check the tightness of all components, especially the top nut under the hood and the preload setting.
How often should I adjust my coilover settings?
Once you find a setup you like for daily driving, you likely won’t need to adjust it often. You might change damping for a track day or adjust height if you change wheel/tire size. Otherwise, just perform periodic checks for tightness.
What’s the difference between height adjustment and preload adjustment?
Height adjustment moves the entire shock in its mount, changing car altitude. Preload adjustment changes the initial tension on the spring itself. They are separate adjustments on most Truhart kits, and you should adjust height first, then set preload.
Taking the time to adjust your Truhart coilovers properly makes a massive difference. It transforms them from just a lowering kit into a precision handling tool. Start with a conservative height, set preload correctly, and patiently tune the damping. The result will be a car that not only looks great but drives exactly how you want it to. Remember, safety is paramount, so if you’re ever unsure about a step, consulting a professional mechanic is always a smart choice.