sorry to revive such an old topic, but i have the same problem..

i have an 07 g35 coupe and this is happening to me. i recently brought it in for the 30k maintenance.. and told them about the squealing noise.. as part of the 30k maintenance, they said my drive belt was cracked and had to be replaced.. i replaced it, hoping that would also fix the squealing noise..

so after all the checks, my brakes are fine.. drive belts replaced.. and noise is still there..

help?

 

^belt tensioner pulleys, alternator bearings. having my alternator replaced next week.

 

how much are alternator?
i've taken it to a few dealers and they don't know what's wrong.. what should i do?

 

I can sell you an alternator for $100 shipped. It has around 85,000 miles on it.

 

do you have an independent mechanic you can go see to tell you what the real problem is first? do not trust the dealers. they once told me my cats were going bad because of a engine code. little did they know that I had relatively newer Crawford Cats. the engine code was thrown by a low voltage problem due to the cheap factory battery. problem was solved with a new Optima Red Top. only had 25K on the car at the time.

my alternator bearings are going bad most likely from the dealer over tightening the belts. my indy mechanic said the belt tensioner was all the way out and probably stessed the internal bearings causing early failure of the part. in fact it caused my accessory and idler belt tensioner pulleys to go bad early as well. these parts should not all be failing @ 30K miles. kind of a funny coincidence. know the dealer will not cover under warranty because I have UR pulleys. they will blame it on that. but it is my fault. last time I was at dealer for a broken door lock actuator I asked them to tighten the belts because I was getting a little chirping upon cold start ups. this was well over a year ago as I never go to dealer unless it is a warranty issue. did not know they would crank my belts all they way out and probably why the belts went bad tto early as well. should have just let my mechanic handle it at next oil change. live and learn.

if it is an alternator, you can get a new one from Coz @ www.conceptzperformance.com for less than what dealer would charge. retail from dealer is like $350, which is a rip off. Coz can get you a much better deal. you could by a re-manufactured one for cheap...google G35 alternators. or you could buy a used one from someone on here for real cheap. make sure it is the alternator first and not just loose belts.

 

I think I'm having a similar squeak/squeal issue with my g35. I sprayed some WD40 on the inside of the belt and the noise did go away, does that mean the issue is with the belt (and not something it's...belting)?

 

Is your belt old/worn? Is it loose? I would tigten rather than spray WD40. I don't think that is a good idea...

 

Hey, I'm not sure of the belt's age as I got the car used. How should I test the tension (I read about how it should bend in the middle, but how much pressure should I apply)? I'll read up on how to tighten the belt.

 

Is the belt cracked or torn? You should be able to turn the belt to about a 45 degree twist. Tightening the belts are fairly easy, if it's your first time being under the car make sure you use jack stands!