Noisy motor sounds like motor bearings are dry

Unfortunately those machines do not have serviceable bearings. The entire motor needs replaced. However, I have saved noisy bearings by putting oil on them, specifically 3 in 1 Blue Label motor oil. A few drops spread on the top and bottom of the bearings and giving the motor a few backward and forwards turns by hand will help those bearings immensely.

if you get the motor out and it's not a sealed unit you can replace the bearings there should be a number on the side ,if not you need to measure inside and outside diamiter also the width you can get them off ebay or this link below
https://www.google.co.uk/search?q=roller+bearings&hl=en&tbo=u&rlz=1T4GGNI_enGB515GB515&tbm=isch&source=univ&sa=X&ei=aFvkUKOcApS1hAes7oDgBA&ved=0CGcQsAQ&biw=1280&bih=632#hl=en&tbo=d&rlz=1T4GGNI_enGB515GB515&tbm=isch&sa=1&q=sealed+roller+bearings+size&oq=sealed+roller+bearings&gs_l=img.1.1.0i24l2.23732.42093.0.49482.7.7.0.0.0.0.131.496.6j1.7.0...0.0...1c.1.q2uOaSowIkM&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&bvm=bv.1355534169,d.d2k&fp=a641b9f2373eac9&bpcl=40096503&biw=1280&bih=632

sounds like an obstruction in the blower motor fan or bad bearings in the blower motor located in the bottom end of the main body

I have the same problem with a CTC Shop Vac. It's he bearings ... they're worn out and dry ... no lubrication. I've trid taking the motor apart and lubricating the bearings, then it runs super for a few uses but then the squealing starts again. Oitch it and buy a new one.

more than likley its the motor bearings wearing out and the brush bearings as well by now

the motor bearings are starting to fail most likely. You can diagnose the source of the noise by removing the brushroll and belt, could possibly be the brushroll bearings but if you still get the noise when the belt is off its the motor.

is the vacuum new how old is it, it may be time for a new vacuum or check on how much new motor is to replace it.

Try blowing out the motor housing with commpressed air through the cooling vents as it is running, if that dont quiet it down it may be the bearings are dry and need to be oiled, use 20w 3 in 1 oil in the blue container.

Sounds like a bad motor bearing. If it is, then you would have to replace it. Could be the brush roll, did you check the ends to make sure they turn easily?

Usually when the motor fan or motor bearings go bad, it will run very loud. You will have to replace the motor. Part #2031214, sells for around $55.