Maintaining classic car shock absorbers is essential for preserving both ride comfort and safe handling. Unlike modern vehicles, older suspension systems rely heavily on regular inspection and care, as components naturally wear over time.

Shock absorbers control the movement of the springs, preventing excessive bouncing after hitting bumps or uneven road surfaces. When they begin to fail, you may notice increased body roll, poor road holding, longer stopping distances, or uneven tyre wear. These are clear signs that attention is needed.

Routine visual checks are a good starting point. Look for oil leaks around the shock body, as this often indicates internal seal failure. Worn mounting bushes or loose fittings can also reduce effectiveness and should be replaced promptly.

On classic cars fitted with lever-arm shock absorbers, checking fluid levels is especially important, as low fluid can significantly reduce damping performance.

Regular road testing is equally valuable. If the vehicle feels unstable, bounces excessively, or produces knocking noises over bumps, the shock absorbers may be worn. A simple “bounce test” — pressing down firmly on a corner of the car — can also reveal issues if the car continues to oscillate after release.

Maintenance should also include keeping all mounting points clean and corrosion-free. Rust can weaken suspension components and make removal or replacement more difficult. Applying suitable protective coatings can help prolong the life of these parts.

Where possible, original-style replacements or professionally reconditioned units are recommended to maintain authenticity and performance. Specialist suppliers often provide refurbished shock absorbers tailored to classic models.

By carrying out regular inspections and addressing issues early, classic car owners can ensure their vehicles remain comfortable, stable, and safe to drive, while preserving their originality and long-term value.

Vehicle suspension not only ensures driving comfort, but also provides good road holding. The springs themselves are responsible for absorbing bumps in the road surface. The vibrations that arise from this are reduced by shock absorbers.

Suspension Systems

Most cars have steel springs. The oldest type is the leaf spring. The uppermost and longest leaf, known as the main leaf, has an eye at each end for mounting to the chassis. The additional leaves underneath are shorter and less curved.

When the suspension compresses, the spring forces are transferred from the main leaf to the individual auxiliary leaves. This is known as progressive load absorption. Other types of vehicles use coil springs and torsion bar springs. The torsion bar suspension consists of a bar that is splined at both ends or shaped with a square section. One end is fixed to the wheel arm, the other to the chassis. The vehicle’s weight twists the bar and is absorbed in this way.

Rubber block springs can perform the same function, but they are not capable of compensating for large forces and are therefore only used in lighter vehicles.

For this reason, rubber block springs are sometimes combined with sophisticated hydraulic systems. In such a system, the up-and-down movement of the wheels pumps hydraulic fluid from one chamber to another through a valve damping system. Each chamber contains a flexible membrane that compresses gas on the other side. As hydraulic fluid flows into the chamber, the compressed gas takes over the springing function.

If the front and rear spring elements on each side of the vehicle are connected, the suspension travel is equalised.

The hydraulic suspension used in Citroën vehicles can be specially adjusted with a pump to increase ground clearance.

When a car drives over a pothole, the spring is first unloaded and then compressed again. The resulting vibration does not quickly subside due to the energy stored in the spring. This leads to very unstable driving behaviour, poor road contact, and, over time, uneven tyre wear.

For this reason, all modern suspension systems are equipped with a damping system.

The shock absorber contains a piston that moves up and down inside a sealed, oil-filled cylinder. It is fitted with special valves through which the oil must flow during this movement. This process is damped, meaning it occurs slowly. In this way, the oscillations of the springs are reduced and the vehicle continues to travel smoothly.

There are three different types of shock absorbers used in modern vehicles:

Telescopic shock absorbers, which slide into one another like a telescope. One end is mounted on the axle, the other on the chassis.

Struts, which are similar in design but have the shock absorber integrated into them.

Lever-arm shock absorbers, which are now rare. In this type, a special lever moves a piston inside a shock absorber housing mounted on the chassis.

Some vehicles are equipped with special gas-pressure shock absorbers, which are particularly effective.

Stabilisers

To prevent excessive body roll, stabilisers are fitted to both the front and rear axles.

These consist of a torsion bar connected to the axle components and the chassis via pivot points. When one side of the vehicle compresses, the forces must first overcome the torsional resistance of the stabiliser.