My 24-70 felt a little rough when operating the zoom ring. So without further use, I decided to do the re-grease service. This is not rocket science and if your careful, is a straight forward job. OR you could spend a few hundred dollars and let/wait for Nikon to do it.

The lens front.



Under the front thin cover are three gaps. These are where the cover can be lifted.



Cover removed showing the three screws to be removed.



Remove the screws and carefully remove the front element. There are shims under the front element housing ring. The value of the shims on my lens can be seen pencilled on the front rim. (done during calibration at the factory). Mine are 0.35mm.



Inside the lens with the front end removed. You can see the guide tracks/grooves in the inner wall of the body.



It is these that need to be greased. DO NOT USE OIL!!! The only safe grease to use is Lithium. It's temperature range is correct and it wont gas off inside a hot lens.



I apply it with a cotton bud. Use it sparingly. Any old grease must be wiped off prior to new grease application. Again, use cotton buds to do this. ONE WIPE each end and bin. Don't double wipe a used end/tip.

Work the lens gently after greasing and look for any displaced grease forced from the groves or sides. Gently remove the excess with clean buds.

It makes a world of difference and the lens is back to silky smooth, as new.

Carefully re-assemble the lens. Screw are snug not hard tight!

Best regards