A 70-300mm lens. Makes a grinding noise when the lens is extended. It no longer extends itself automatically

SOURCE: Lens not Extending

this problem is caused because that the lens servo can`t move the unit of lens. this menssage mean that the sistem don't go out the lens. You have to sincronise the mechanism of the lens, carefully disarm the unit and review that the gears are ok.

SOURCE: Hard to extend zoom

Hate to say it, but unless you have a bunch of experience with lens assemblies, your best bet would be to take it to a camera or photography shop to have them look at it. You need the right sized spanners and such for disassembly. There are also a number of considerations to be taken into account when reassembling them. They shouldn't charge for looking at it and can give you an idea as to what it would cost to have them fix it. From what you've told us, it sounds like it's gummed up and may just need to be cleaned.
Ron-

SOURCE: fujifilm A345 camera

does this carmea have a zoom on it]

SOURCE: EF 24-70 lens droop...

The zoom creep is an easy fix for Canon. I really do not recommend trying to tighten it yourself, since that would void your warranty.
It is usually free to tighten the zoom ring.
/Chris

SOURCE: Olympus Zuiko 70-300mm lens focus question

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