Turbo makes a buzzing or rattling noise
 

I have a 88 tll and every time the turbo is boosting around the 4500 rpm range its starts to make a rattling noise. Is this normal or is something wrong?

Thanks.

check your shaft play!
this is accomplished by taking the Turbo Intake Duct off of the Turbo (with car off and cool) and checking the amount of up/down motion of the compressor blade! not in and out it would be up/down or side/side motion! if it moves too much then you are in need of a rebuild!

What about your Heat Sheilds? They would rattle If they were they not mounted tight.

If i had shaft play wouldn't i be noticing something else major? Like different amounts of boost being produced. Because it always boosts to the same amount.

Turbos don't buzz and rattle. Turbo heat shields buzz and rattle... ;)

well I don't know about that NZconvertible;
my turbo went rattle when it crashed... mind you it crashed hard... But would th heat sheilds really make that huge of a racket? I know mine didn't and they were pretty loose. they only rattled at idle... That is why I didn't think it were those!

It the heat shields arent too loose you can hear them rattle when starting and when you turn off the car or if your engine rpms are really low and the motor is struggling.