my 01 gs430 with 60k started to make high pitched noises like birds chirping when it is first started cold- the serp belt looks ok, no cracks- the dealer said it was replaced at 30k and it shouldn't be bad already. would it be the tensioner? is this easy to replace and DIY? Any other suggestions? Thanks.

 

First time I heard that noise I thought it wasn't the belt either. The belt looked fine...no cracks. But I replaced the belt and the noise went away. I came to the conclusion that the felt on the belt slowly wears away and when it's gone....the belt slips a little. Like clockwork, every 30,000 miles it wears out...but it's a cheap part.