I have 2 turbine roof vents. One is very noisy when it spins, but only sometimes, depending on temperature. Not squeeling, but more of a rubbing or grinding type noise. What does it need? Lubrication? If so, is it best to approach from the attic, or on the roof?
Thanks

First approach from inside the attic and have a good drop light with you. Sounds like it is bent or out of balance and spinning like a lazy top. Start there and come back with what you see. Lubing alone will not cause or cure that rubbing sound unless it is a totally shot bearing. Then of course totally shot can't be broght back to life either with lube.

Seems to be spinning true, but was able to approach from inside the attic and foung that with a good application of lubricant it is silent. Seems to be all it needed.
Thanks

Have 4 turbines on the roof of my quad villa.
My neighbor and I have been complaining of lots of noise from these things. Maintinance capped two of them in my living room area. Did not cap the two where our bedrooms join. Sometimes very noisy. They say not turbines causing noise. Thanks for any help you can give me. They did oil them but didn't help. Our community is approximately 35 years old and my guess is these are the original turbines.