Hi, I'm Steve and I am fairly new to the 175 club and my 175. My question is, does anyone else have what seems to be gear backlash in flight when the prop isn't pulling hard? It doesn't happen all the time, just every so often. It doesn't seem to hurt anything so far, but my brother-in-law says it sounds like a baring race starting to spin. I think it sounds like backlash from the gear reduction prop in an idle period. When it is pulling at all, no noise. Any ideas?

Welcome Steve....If you are at low rpm settings and sometimes in a strong crosswind you can hear the backlash from the gearbox. Normally when I start hearing it I just push the power up a bit and it goes away.

Don't let the gears slap. Those gears can take a lot of force either way, but not at a no load condition with the engine pulses banging on them. Slapping a loose gear like that is like hitting it with an air chisel or a slide hammer.
Set your idle to factory spec's
check you tach to make sure it is accurate - remember the "c" model reads prop speed the rest read motor speed - so set it to the correct speed for your model.
The loose tolerance can change with temperature
KenW

Thanks Rick and Ken for your responses. At least now I know we aren't the only 175 owners who have this noise. I don't here it much anymore because I try to keep the airplane pulling to avoid that, but my brother-in law seems to have a real problem with it. I'll have to tell him he is allowing it him self. He's probably not going to take my word for it though. It's coming up for annual in July so everything should get readjusted to spec.

I think the 175 is a great airplane and next month I'm taking it to Idaho for some mountain flying. Thanks again.

Steve
I find that if you pull the power off to fast in flight you will get that. Pull power slowliy and you should not hear it. Keep some power on landing so gear is on thrust brg. even though you have 1500rpm showing your prop is not at 1500.
175's fly great in mountins ,Remember to lean or you will be cleaning the belly. run it full power and it will do fine. I fly off 6820 ft. airport so every thing is up in alt from here where I fly.

Thanks Jim, All advice is appreciated