What Causes Car Noises?

[DeDeclan]

The reason for a thumping sound when the car is running is: If it accompanies the change in vehicle speed with a periodic rhythm, it should be abnormal noise caused by rotating components such as wheels or drive shafts. Key inspections should focus on whether the rotating components like wheels or drive shafts are abnormal and whether there is any movement interference with surrounding fixed components. Below is extended content: 1. The drive shaft is a high-speed, minimally supported rotating body, so its dynamic balance is extremely important. Most drive shafts undergo dynamic balance testing before leaving the factory and are adjusted on a balancing machine. 2. For front-engine, rear-wheel-drive vehicles, the drive shaft transmits the operation from the transmission to the main reducer's shaft, which can consist of several sections connected by universal joints.

[Paula]

Last week while driving, I noticed a squeaking noise coming from the car's chassis, especially noticeable when turning. This situation might be caused by aging components in the suspension system, such as dried-out shock absorber bushings or loose ball joints on the control arms. It could also be vibration noise from worn exhaust pipe hangers, as metal parts develop gaps over time with use. During the last maintenance, the mechanic mentioned that such noises are mostly due to aging rubber components, and avoiding bumpy roads during daily driving can help prolong their lifespan. It's recommended to first check for any noticeably loose parts yourself. If the abnormal noise persists, it's best to get it inspected at a repair shop as soon as possible—chassis issues shouldn't be taken lightly.

[MaggieRose]

There's always a rattling sound in the back seat of my car, like plastic parts are having a disco. The most common causes of such noises are loose interior panel clips or seatbelt buckles hitting the B-pillar. Even coins in the seat rails can make noise. An unsecured toolbox in the trunk can also bang around, and even the sunshade hinge under the rear windshield might creak on bumpy roads if it lacks lubrication. Identifying the pattern is crucial: does it only happen over speed bumps or at certain speeds? I recommend organizing the cabin clutter and pressing on interior components to locate the source. If the noise persists after a few days, it's likely necessary to remove the interior panels and reinforce the clips.

[Maeve]

The screeching noise from the engine bay is the most annoying. I've experienced it when the alternator belt slipped. Opening the hood to pinpoint the sound source is crucial: short metallic knocking may indicate a failed tensioner pulley bearing, while a buzzing resonance often points to water pump or alternator bearing issues. Belt-related noises are usually more noticeable when the engine is cold, as the rubber softens and quiets down when warmed up. Check for cracks, shiny spots, or oil contamination on the belt. Applying belt dressing can provide temporary relief, but replacement is the permanent solution. Remember to turn off the engine before inspection - rotating parts are dangerous.