I brought Nissan maixma SL 2017, Feb and I have 13k now.
After I drove about 3k, I start hear the whistle noise from the hood (around 30 -70 mph) only when I accelerate (sounds like leaking). Problem is, sometime I can hear noise but sometime i can't...
I took a service and they told me that it was a transmission problem
I was not happy for brand new car, but they told me they will put new transmission.
2 days later after I received my car from service, I heard the noise again.
Engineer from the nissan came down to service center and drove my car, and he said it has no problem to drive... (He said All CVT make that noise...).
They dismissed my case.. what can I do for this case?
I drove different Maxima and didn't make any of whistle noise...

Did anybody had this kind of issue? I'm getting really tired of whistle noise.. Please help!!

 

Stretching a bit, this may have nothing to do with your problem, but last year my 2007 Vette started making this whistling noise, but not always. Happened at about the same speed as you indicate. Sometimes sounded like it was coming from under the hood, and at other times it seemed to be coming from the front windshield area. Drove me nuts. I finally figured that the noise happened when I was driving into the wind, if you can believe that! It seems that the noise was wind related and was caused by an ill-fitting piece of black molded trim on the cowl under the wiper blades. At the right "air speed" the wind was causing a harmonica affect with that ill-fitting piece of trim. To test my theory I just applied a strip of tape to the trim and that stopped the noise. Removed the tape and applied silicone adhesive to the underside of the seam area for permanent repair. You never know................., but I can't believe those dealer techs replaced your trans over a whistling noise. That makes no sense at all. Such a waste of your time and their money. Might be our money the next time we buy Nissan car or part. BTW, we both have the same year, model and mileage.

 

I think compyelc4 may be headed in the right direction.

With several of my Maximas of past generations, after I installed rain guards, I began hearing excessive noise, sometimes just a 'rush', but sometimes sort of a whistling noise. Knowing I had done nothing but add rain guards, I experimented with small baffles in front of the leading edge of each rain guard. I found a shape and size that cancelled out the wind noise the rain guards were causing.

If I were you, per compelc4's experience, I would first try driving both into and away from the direction of a brisk wind. If heading into the wind nade the noise worse, I would begin trying tape over areas just in front of the windshield until I narrowed down the source, etc, etc. Once the source is found, it should not be difficult to use tape or baffles or silicone, etc, to quiet the noise.