If you have a noisy focus ring on your Canon EF 24-70 f/2.8L II, below is the reason why. The report is dated February 2014, so all lenses manufactured prior to August 2013 are are potentially affected. I've had first hand experience with this issue from our rental inventory. I have no idea if Canon will charge you for this repair if the lens is out of warranty. We haven't bothered to fix our inventory, as a few lenses have exhibited the issue, but functionality doesn't seem to be affected.
Repair Information
It has been confirmed at the factory that when turning the focus ring, in rare cases, an abnormal noise can be heard. If units are brought in due to complaints of this nature, please replace the part with the new part.
Compatibility
Old and new types are compatible.
Time of Change
The new type has been incorporated into products from the August 2013 production.
When mounting the new SPRING, COIL (CB3-3809-010), there is no need to mount PLATE, SPRING HOLD. (There will not be problems even if the PLATE, SPRING HOLD is mounted.)
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