I heard the high pitched squeal today

[sdtag]

I had my P2V+ hovering at about 6 feet so I could check it out. I heard the high pitched squeal that I read about here I think about a month ago or so.
I bought my Phantom in March. I think I have recorded just about every flight. I am up to DJI00425 which means I have over 400 flights on my Phantom. I have no idea of the total flight hours, most of my flights seem to be 5 minutes or less. 400 X 5 = 2000 minutes divided by 60 = 33.33 hours in the air. Probably closer to 20 or 25 really.
I have seen or read about folks trying to oil the bearings in the motors and to be honest I haven't looked that closely at the motors, but I thought the motor bearings were sealed. Oil wouldn't do anything but make a mess.
So here is my question: does anyone think it's time to replace all 4 motors? I think they are like 20-25 bucks each. For a hundred bucks I could have peace of mind.
anyone? thoughts?
TIA

 

[RoyVa]

The motors do have sealed bearings and these motors are brushless. That mean they only have an armature and use magnets with pulses. They are designed to last hundreds and hundreds of hours. I only replace mine due to damage or when replacing an ECS. The high pitched whine can be from the props too. Get a little nick and they can sometime sing too. Use your fingers and turn the motor shafts. See if they are free and all feal like they have the same resistance. Make sure you don't hear any grinding notice like grit or sand in them. If they turn freely then prop up and outside see if they start at same time and stop at same time when powered mor down. If the do fly and have fun.

 

[sdtag]

thanks Roy.
Yes they all feel the same when I turn them by hand and they all fire up and stop at about the same time. Maybe the noise has been there all along and I never noticed. If they are meant to last hundreds of hours I guess I won't worry too much about my 20 hours so far. haha
It might be my props. I'll try another set. I also have some carbon fiber props, discussed in another thread. I'll try those too. I must have lucked out because my quad flies just fine with the carbon fiber props.

 

[BlackTracer]

I don't know if this is relevant but mine has whistled ever since I got it back in May of 2014. Mostly when it decelerates. Not just sitting there hovering. I think this is different than yours as mine is not a squeal, but a whistle. It has always flown like a dream so I have kept the original props on it all this time, not caring if it is the props that whistle.

 

[RoyVa]

Dafter you flight just check the motors for heat and make sure it's not really hot, from a bad bearing or a bearing starting to seize. If they are not rally hot and stil turn free. Should be good to go.