Hit a Curb or Pothole? What to Check on Your Coilovers
After you hit a curb or a pothole, check the tire and wheel first, then the suspension. If the car pulls, the wheel sits crooked or a damper looks wet, inspect your suspension after hitting a curb before driving hard again.
Most hits do no lasting harm. Some bend a part you cannot see from the driver's seat. A lowered car on a coilover kit adds a few checks of its own: the damper shaft, the seals, the locking collars and the mounts. Here is the order we would check them in.
Stop Driving Right Away If You See These
Some signs mean the car should not go anywhere except on a truck or, at most, slowly to the nearest shop. Check these at the roadside before anything else.
Tire damage
A bulge or bubble in the sidewall, a cut, or a tire losing air. Fit the spare or call for a tow.
Wheel or steering trouble
A visibly bent rim, a wheel that wobbles, or a steering wheel that is far off center or feels loose.
New sounds or stance
Grinding, a heavy clunk over small bumps, or one corner sitting lower than the others.
Warning lights or fluid
An ABS or stability warning that was not there before, or fluid dripping near a wheel.
If none of those show up, you can usually drive gently home or to a shop and do the full check there. When in doubt, do not drive it.
Checking Suspension After Hitting a Curb: The Walkaround
Start with the car parked on level ground, wheels straight. Use a flashlight, even in daylight.
Tire. Look at both sidewalls, inside and out. Check the tread for fresh cuts. Check pressure against the door placard.
Wheel. Look for flat spots or cracks on the inner and outer lip. Check that every lug nut is still tight.
Arms and links. Look at the control arms, tie rod and sway bar end link on that corner. A fresh scrape, a kink or a bent bracket tells you where the force went.
Stance. Step back ten paces and look at the car from the front and rear. A wheel leaning in or out more than its partner on the other side is a clue.
The parts that take the hit first are unsprung weight: wheel, tire, hub, brakes, knuckle and part of the arms and damper. That is the mass the springs do not carry, so it gets the full shock of the impact. Damage usually starts there and works its way up.
The Drive Test: Pull, Steering Wheel and Vibration
If the walkaround looks clean, take a short, slow drive on a straight, quiet road.
Steering wheel off center. If the wheel now sits crooked while you drive straight, toe has changed. That points to a bent tie rod or arm, or a shifted alignment setting.
Pull to one side. A new pull after a hit points to an alignment change on that corner. It can also be a damaged tire.
Vibration at speed. A shake that grows with speed often comes from a bent wheel or a tire with internal damage. Have both checked on a balancer.
Any one of these means an alignment check at the least. Our guide to suspension geometry coilover failure explains the knock-on effect. A bent part left in the car keeps loading the coilover wrong until something else wears out.
Coilover Checks: Shaft, Seal, Collars and Mounts
Now the coilover itself. Get the wheel off if you can, with the car safely on stands.
Bent damper shaft
Look at the shiny shaft where it enters the damper body. Check the gap between the shaft and the body all the way around. If the gap looks uneven, or the shaft shows fresh scoring, suspect a bend. A bent shaft can bind and will wear the seal. That damper needs a rebuild or a replacement, so do not drive the car hard on it.
Leaks at the seal
Wipe the damper body clean and look again after a short drive. A wet, oily film running down from the top of the body, with dirt stuck to it, points to a leaking seal. A light film of dust is normal. Oil on the outside means oil missing from the inside, and damping goes with it.
Locking collars and ride height
A hard hit can shift a collar that was not snug. Measure ride height at each corner and compare it with the numbers you wrote down at install. Our guide on how to set ride height on coilovers covers how to measure. Check each locking collar is tight against its partner. If one corner has dropped, reset it and recheck the rest.
On full-length kits like BC Racing and Fortune Auto, ride height is set at the lower mount, and the spring perch sets preload. Check both sets of collars. Also make sure the spring still sits cleanly in its perch and upper seat.
Top mounts and lower brackets
If your kit has adjustable camber plates, check whether the plate has slid in its slot. Check the mount bolts are tight. Look at the lower bracket where the coilover meets the knuckle for bends or cracks. A damaged mount is a part you can replace on its own. Öhlins, for example, sells an adjustable front left strut mount for the 2008 to 2021 WRX and STI (GR/VA) as its own part.
New knocks or rattles after a hit deserve their own hunt. Our guide to coilover noise walks through the usual suspects.
Sensors, Brakes and Hidden Damage
Check the ABS wheel speed sensor cable on the corner you hit. The sensor and tone ring move together with the hub, so the gap between them does not change with height. The real risk is a cable that got stretched, pinched or pulled loose. A new ABS light after a hit usually starts there.
Look at the brake line and the brake hose too. A hose that rubs a tire or a coilover body after a hit needs fixing before the car goes anywhere. Passive coilovers have no wiring of their own, but cars with adaptive dampers do, so check those connectors if your car has them.
Repair, Rebuild or Replace
Get an alignment after any hard hit, even if the car feels fine. If the shop cannot reach a setting it reached before the hit, suspect a bent part. Fix that part first, then align.
For the coilover, a bent shaft or a leaking seal usually means a rebuild or a new damper. Our guide to coilover rebuild choices covers the options. Each brand handles service its own way. Fortune Auto states it rebuilds and revalves kits in-house at its facility in Powhatan, Virginia. BC Racing replacement parts can typically ship directly, so you do not always send the full kit away.
Single parts are often available too. We list individual BC Racing springs if a spring was damaged; give us the spring rate, size and coilover part number when you order. Swift Springs SPEC-R springs are an upgrade option on most BC Racing fitments if you would rather change the springs at the same time. For KW, Öhlins, Bilstein and the rest, call us and we will check parts with the brand. Check your brand's warranty terms before you assume a curb strike is covered.
Preventing the Next One
You cannot avoid every pothole. You can make the next one cost less.
Keep ride height sensible. Every inch you drop takes clearance away, and on perch-only kits it takes bump travel too. A modest drop leaves room for the suspension to absorb a hit before something solid makes contact.
Keep the threads clean. Grit makes collars hard to set and easy to miss when they loosen. Our Coilovers.com coilover socks and Fortune Auto protective coilover covers wrap the body and spring to keep grime off.
Write your settings down. Ride height at each corner, damping clicks and alignment numbers. After a hit, you will know in two minutes what moved.
Good performance suspension forgives a lot, but not everything. A careful check after a hard hit protects the coilover kit, the car and the tires.
Frequently Asked Questions
How do I know if I damaged my suspension after hitting a curb?
Watch for a steering wheel that now sits off center or a pull to one side. A new noise, vibration at speed or one low corner count too. Then look at the tire, wheel, arms and coilover on that corner. Any of those signs means an alignment check and a closer look.
Is it safe to drive after hitting a pothole?
Only if the tire, wheel and steering look and feel normal. A sidewall bulge, a bent rim, a loose or badly crooked steering wheel, grinding, or a new warning light means stop. When in doubt, fit the spare or get a tow.
Can hitting a curb bend a coilover?
Yes. A hard hit can bend the damper shaft or a lower bracket. Look for an uneven gap where the shaft enters the body, fresh scoring on the shaft or a bent bracket. A bent shaft will wear the seal, so get it rebuilt or replaced.
Do I need an alignment after hitting a curb?
Get one checked, even if the car feels fine. A hard hit can shift toe or camber, and a small change still wears tires fast. If the shop cannot reach the settings the car had before the hit, a part may be bent and need replacing first.
Why did my ride height change after a pothole?
A collar that was not fully snug can slip under a hard hit. Measure each corner, compare with your install notes, reset the corner that moved, and tighten the locking collars. Then recheck the alignment, because height changes alter camber and toe.
Why is my ABS light on after hitting a curb?
The wheel speed sensor cable on that corner may be stretched, pinched or unplugged. The sensor gap itself does not change with ride height, because the sensor and tone ring move with the hub. Check the cable routing and connector, then have the code read.
Is curb damage covered by coilover warranty?
Check your brand's warranty terms before you assume so. Each brand sets its own coverage. Call us with the brand and part number, and we will help you sort out the repair path and parts.
Hit Something Hard? Talk to Us Before You Order Parts
Tell us the brand, the part number and what you found on the walkaround. We will help you work out whether it is a collar, a mount, a spring or a damper. Then we will sort out what it takes to fix it.
Call 1-800-460-9106 and we will help you sort it out.
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