I own the Canon EF100-400mm L IS USM
lens. I've had it about 3½ years now and she's starting to play up!! The locking ring seems more and more tighter and the sliding action of the barrel is tighter still. I've heard it can be the bearings seizing, does anyone have the same issues and if so what did you do about it? BTW, this isn't a free for all have a dig at Canon thread!!!
EOS1D4, 7D, 30D, 100-400/4.5-5.6 L IS USM, 70-200/2.8 L IS2 USM, 17-40 f4 L USM, 24-105 f4 L IS USM, 85 f1.8 USM