Last month, I started to notice a distinctive “whirring” / “knocking” sound coming from the left passenger-side wheel on my car. At first, you could barely hear it, as the engine masked its presence. However, as time went on, this squeaking sound became louder, causing me a great amount of worry.
The first thing I noticed was that the sound was louder and more prominent when I was driving at a slow speed. Basically: The faster the car went, the less noticeable it was. At slower speeds, the sound would become unbearable and embarrassing (kind of like how wet runners sound when they squeak on a wooden floor)!
Anyway – my first assumption was that the bearing had gone. A few days beforehand, while turning a sharp corner, I heard a loud snapping noise, which seemed to have emanated from the wheel in question. While googling around some of the various car help forums, I (falsely) came to the conclusion that the bearing had completely gone.
Fortunately, this was NOT the case. After I took off the hub caps to take a better look, I noticed that THREE of the nuts on my wheel were loose! A few weeks beforehand, I had to replace all of my tires in order to pass the NCT test in Ireland, so I’m guessing I didn’t do a good enough job of ensuring that they had been fitted properly (you’re supposed to keep an eye on them for a few days, lest one of them becomes loose)! The reason the sound was more distinctive at slower speeds was because there wasn’t enough force to “lock” the wheel in places. i.e. It had more leeway.
Conclusion: After tightening the nuts, the sound disappeared completely.