EXTERIOR NOISES

1. Front hubs

A worn suspension balljoint, kingpin or trunnion will cause a knocking that resonates through the body (best detected with the windows up).

Shock absorbers

A heavy bang or a machine-gun rattle might be the shock absorbers. Don’t condemn the unit itself before checking its top and bottom fixing bolts are tight and there’s no play in the bushes.

Fittings and fixtures

Other light exterior rattles probably emanate from loose bumpers, grilles, roof racks or similar. Make sure everything’s tight. Check for bumper bolts that have partially unscrewed then seized.

Road springs

Coil springs are silent unless broken. So are leaf springs, unless they’re really neglected. Worn or dry spring eye bushes, however, can squeak like mice. Rubber bushes might fall silent in wet weather.

Exhaust

The most common source of heavy knocking is the exhaust hitting the underbody, often on large bumps or when pulling away. Slacken clamps and rotate sections until the correct fit is achieved.

2. Brake pads

A very light rattle might be the brake pads. These should have wire clips fitted to prevent this. They may be missing or stuck solid in old grease and rust.

3. Trackrods

Trackrod ends produce a lighter sound, accompanied by play in the steering. It’ll clonk when you waggle the steering wheel with the car stationary. Check the track rod adjusters aren’t loose.

Rear brakes

If rear drums rattle, the handbrake expander bar is probably loose. It often doubles as a selfadjuster (check it’s working). Some have anti-rattle devices or rely on correct handbrake adjustment.

Engine and gearbox

Heavy knocking when moving off could also be down to collapsed engine or gearbox mounts. A clack-clack-clack on undulating surfaces may be the propshaft making contact with something.