Possible K-5 WR problem

Hallo PU

I've had my K-5 for service to repair a damaged Viewfinder LCD and Top LCD.

When I got it back, I discovered that the rear wheel, sounded noisier than the front wheel. It is also noisier than the shutter sound.

Now I have discovered that when I zoom my 18-135 WR from 135 to 18mm, says it Pssssss from the left side of the rear wheel, and I have no doubt that air comes out at the wheel.

Is this normal or do you think my gasket at the wheel is damaged?

Regards, M. Fog, Denmark

I would send it back, it certainly doesn't sound right,

+1. If air can be forced out, it can be sucked back in (with dust, water, etc), unless, of course , it's a one-way valve, which leads to the question, anyone know how WR bodies and lenses handle 'pumping'?

Any (non fixed) lens will act as a piston, so air is being pumped in and out as the focus or zoom is operated.

Are there one-way vents to deal with this air movement?

Just my thoughts.

In my mind, there need to be some sort of vents, but i my mind, it should be through a filter of some kind.

and not at the thumb wheel....