Suspension set-up affects how a car holds the road: tyres, wheel angles and the dampers themselves all work together. Adjustable coilovers let you change ride height and stiffness without replacing parts, but only if the threads are clean and the collars are not seized.
In Ukraine coilovers have a hard life: mud, salt and de-icing chemicals pack the threads in winter, and within a season the adjusting collars may refuse to turn. Here is a sequence that helps you change the height carefully and safely.
What you will need
Important: Never work under a car supported only by a jack: always use axle stands. Keep lubricants and degreaser away from brake discs, pads and tyres. Incorrectly tightened lock collars can work loose while driving, which is extremely dangerous.
Step 1
Raise the car and remove the wheel
Park on level ground, apply the handbrake, crack the wheel bolts, jack the car up and place axle stands. Spray seized bolts with WD-40 Specialist Penetrant, give it a few minutes and undo them.
Remove the wheel to gain access to the damper and spring and see the current setting.
Step 2
Clean the damper threads
Brush dried mud off the damper body. Then apply WD-40 Specialist Degreaser to the threads, let it work and remove the dissolved dirt, grease and dust. Clean threads will not be damaged when you turn the collars.
If the collars will not move, apply WD-40 Specialist Penetrant and wait 5-10 minutes for it to work into the corrosion between the threads.
Step 3
Change the ride height
There are two main types of coilover: fully adjustable ones with separate body height and spring preload adjustment, and those with a single collar that changes both via the spring. Usually there is a collar and lock collar below the spring.
Loosen the lower lock collar, rotate the damper body to screw it in or out and change the height, then return the lock collar. Tighten only with proper coilover spanners, using two at once.
Step 4
Set the spring preload
The upper collar sets the spring preload. Loosen the lock collar, move the adjusting collar to the required position and lock both collars against each other with two spanners.
Stay within the limits specified by the suspension manufacturer: too little thread engagement is dangerous.
Step 5
Match both sides of the axle
Dampers on the same axle must be at the same height. Mark positions with a marker and count turns: if you made 5 turns on the front left, make exactly 5 on the front right. Do the same at the rear.
If there is a damping adjuster on top, set it identically on both sides.
Step 6
Protect the threads and refit the wheel
Apply a thin coat of WD-40 Specialist White Lithium Grease to the exposed threads: it stays put in rain and road salt, so the collars will turn easily next time. Wipe off the excess.
Make sure there is no lubricant on the brake disc; if needed, wipe it with a clean dry rag or a dedicated brake cleaner. Refit the wheel, lower the car and torque the bolts to specification.
Tip: Always have the wheel alignment checked after changing ride height: wheel angles change, and without adjustment tyres wear unevenly. Drive the first kilometres slowly and away from traffic to check how the car behaves.
What next
Inspect and clean coilover threads before winter and again in spring. For small suspension parts, hinges and locks, keep WD-40 Smart Straw in the garage.
These uses come from the experience of WD-40 users in many countries. Always follow the instructions and warnings on the product label.
More guides in «How to use».