What Causes Slight Abnormal Noise When Steering a Mercedes-Benz?
2 Answers
Mercedes-Benz steering has slight abnormal noise due to insufficient power steering fluid. Causes of abnormal noise: Insufficient power steering fluid: When the fluid level is low, steering becomes heavier and less smooth, and dry friction can cause abnormal noise. Lack of lubrication in the steering column dust cover: The dust cover is designed to prevent dust accumulation, so the surrounding area tends to gather dust. Without proper lubrication, noticeable friction noise can occur. Applying some grease usually eliminates this noise. Steering shaft sleeve detachment: Although uncommon, many Mercedes-Benz models experience steering noise due to this issue. Airbag clock spring problem: If the noise clearly comes from inside the steering wheel, it is likely caused by a faulty airbag clock spring. Suspension system issue: The suspension assembly typically consists of shock absorbers, springs, top mounts, and thrust bearings. When turning the steering wheel, the tires rotate the suspension system. Common sources of steering noise in this system are the thrust bearings and top mounts. Open the hood and listen for the noise. If it originates near the shock absorber top mount, it is likely due to a problem with the thrust bearing or top mount. Loose or damaged stabilizer bar bushings: These can cause noise not only when steering but also when driving on uneven roads. Loose bushings can be fixed by adding shims, but damaged ones must be replaced. Steering ball joint issue: Problems like wear or excessive play in the ball joint usually do not cause noise when steering while stationary. Ball joint noise typically occurs when driving over bumps. Solutions: If the noise comes from below the steering wheel, check the steering column and car floor mats. Oversized aftermarket mats may contact the steering column, causing friction noise without proper lubrication. Applying lubricant can resolve this. If the noise comes from outside the car, it might be due to insufficient lubrication in the shock absorber thrust bearing. Open the hood and listen for noise near the shock absorber top mount to confirm. If the thrust bearing lacks lubrication, apply grease. If the noise persists, replace the bearing. If the noise is not from the thrust bearing, inspect the stabilizer bar bushings for looseness or damage. Loose bushings can be fixed with shims, but damaged ones require replacement. Dirty power steering fluid increases system pressure, causing a "humming" noise from the power steering pump. Replace the fluid promptly. If the noise comes from inside the steering wheel, it is likely due to a faulty airbag clock spring. Remove the steering wheel, apply grease to the clock spring, and test. If the noise continues, replace the clock spring. Handle the steering wheel gently during disassembly or disconnect the airbag fuse to prevent accidental deployment.
There's a slight abnormal noise when turning. I've driven many Mercedes-Benz cars, and the common cause might be wear in the tie rod end ball joint. This thing tends to make squeaking sounds on bumpy roads or during low-speed turns because dust gets in and causes friction after the rubber protective sleeve ages. Another possibility is that the power steering pump isn't functioning properly, leading to a whining noise due to internal gear wear or insufficient oil. During inspection, first lift the front wheels with a jack and shake the steering wheel left and right to pinpoint the noise location. Mercedes-Benz's electronic steering system is also quite complex; issues with sensors or motors can also produce sounds. Ignoring it can make the steering feel heavier, and prolonged neglect may lead to dangerous steering failure. It's recommended to visit a 4S shop as soon as possible to avoid minor issues turning into costly major repairs. During regular maintenance, remember to check the power steering fluid level and replace it if it's dirty.
