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I recently noticed that when I take a sharp bend (almost a U-turn) around 30–40 kph, I hear a sharp "knock…knock…knock…" noise from the outer front wheel area (that only happens for the left side wheel). It is a front-wheel-drive car.

It only happens in such a sharp bend. So I went to the mechanic, and they tested; however, we were not able to reproduce the issue. So they just guessed that it is the CV causing the noise, but they said that I can still drive until I start to hear more noise even when driving straight.

Today I just lifted the troubled wheel and drove on 2nd gear. I can see that the CV axle is not rotating smoothly. Please check the video I attached (watch and listen carefully around 00:10–00:14). I can hear some "knock…knock…" sound from the gear box area as well.

What would be the reason for the CV axle not rotating smoothly? Is it normal? Can this be related with the knocking sound I hear when turning?


Note: Suspension / steering rack / lower arms have all been replaced with brand new parts recently. I also did a wheel alignment and balancing recently. Lug nuts are properly tighten as well. Also, wheels are not touching the body when turning.

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A worn CV joint is the most likely issue that would cause knocking at full steering lock.

What usually happens is a split forms in the CV joint rubber boot which allows the grease to escape and dirt to get in. When this happens, the CV joint will wear quickly, causing it to not rotate smoothly.

If the split is found soon due to seeing the grease coming out of the split, then it is often possible to save the CV joint by removing it and thoroughly cleaning all of the old grease out, repacking it with new grease and installing a new rubber boot before any damage is done.

If you are getting a mechanic to do the job, then his labour will usually cost more than a new CV joint, so it is probably best to get him to replace the whole joint rather than just cleaning it and installing a new rubber boot.

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  • Thanks for the answer. I will replace the CV joint with a new one to see if it fix the problem.
    – Dilshan
    Sep 1, 2023 at 7:37
  • That's the way to go, once you start getting that sound damage has been done.
    – GdD
    Sep 1, 2023 at 8:23
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    Once you get it properly diagnosed, it isn't a good idea to wait on the repair. The longer you drive with a bad CV joint the more chances you have at damaging other parts (seals). And if it completely fails, it will leave you stranded and possibly cause greater damage.
    – Jupiter
    Sep 1, 2023 at 9:32
  • Forgot to accept the answer. I finally replaced the CV joint and it fixed the problem. Thanks
    – Dilshan
    Jan 3 at 9:29

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