Question 1

When shock absorbers need replacing

Accepted Answer

A shock absorber's job is to damp spring motion and keep the tyre in contact with the road in every condition. When damping fades the car bounces even on smooth roads and rolls heavily through corners. It's not just a comfort issue: degraded dampers lengthen stopping distances, particularly when combined with ABS on uneven surfaces.

Gradual oil leakage is the most common failure. Oil visible on the outer body shows up at the first inspection and confirms the seals have gone. The second common fault is wear to the internal valving — damping works only in one direction or feels uneven. These faults don't always show externally but are felt in the drive.

Shocks are always replaced in axle pairs — same axle, both sides — so damping forces stay symmetrical and the car doesn't pull to one side. A useful rule of thumb is to check shock absorbers every 80 000 km, though cars driven on poor roads often wear them out far sooner.

Question 2

How the replacement is done

Accepted Answer

The car is raised on a lift and the wheels are removed. On the front axle the entire strut — shock, spring and top mount bearing — often has to be dismantled, making the work more involved than at the rear. The old damper is removed and the dust boots, bump stops and top mount bearing are inspected for wear.

Worn support parts are replaced at the same time — the top mount bearing is usually the weakest link and causes rattles before the damper itself fails. Springs are checked for breaks — a broken spring is always replaced. The new damper is fitted at the original mounting points and the bolts are torqued to specification.

A wheel alignment follows, as dismantling the strut always affects wheel geometry. During the test drive we confirm damping feel, the absence of noises and correct ride height. A good installation is immediately noticeable — the car feels more settled and composed.

Question 3

Why do shock absorbers stop working?

Accepted Answer

The most common cause of shock absorber failure is seal wear that allows the oil to escape. Without oil the piston can't damp the spring and the car bounces on road irregularities. Another common fault is wear or seizure of the internal valving — damping force disappears in one direction only and the fault is harder to detect. In winter conditions corrosion of the outer body also shortens life, particularly when dust boots are broken and road salt attacks the piston rod. For these reasons an inspection is worthwhile any time the strut is dismantled, even without an obvious symptom.

Shock Absorber Replacement in Vantaa