Why does my office chair creak when I lean back?

Almost always the tilt mechanism. Its nylon bushings have worn, so the steel parts they were separating now rub directly against each other. Less often it is loose seat-plate bolts, which is the easier problem and worth ruling out first.

Why it happens

The tilt mechanism is a stamped and welded steel housing carrying a coil spring and a pivot. Nylon bushings sit at the pivot points to keep steel off steel. They are a wear part, and once they thin out the two steel surfaces touch and stick-slip against each other — which is the creak you hear.

The reason creaking usually means the end of a chair is that tilt mechanisms are typically riveted rather than bolted, and they are model-specific rather than standardised. Unlike a gas cylinder, you generally cannot buy a generic one.

What to do about it

1. 1Turn the chair over and check every bolt where the seat pan meets the mechanism. Loose bolts are common and produce a very similar noise.
2. 2If the bolts are tight, work out whether the noise tracks the tilt pivot or the seat plate by leaning back slowly with a hand on each.
3. 3Lithium grease at the pivot points often quiets a worn mechanism for months. It is a reprieve rather than a repair — the bushings are still gone.