I've had my used 2008 G37s Coupe w/106K for a couple of years now, and maybe it's always been this way, but my old age is getting tired of the droning sound at speeds of 70-80mph. I used to own a 2003 G35 and don't recall it being that noisy. I measured about 79-80 db with a sound meter on my phone; about 50 db at idle. The droning sound increases as I increase speed. At idle is sounds fine and isn't sputtering or anything. Haven't had any exhaust work done or any performance mods, to my knowledge; everything looks to be original. Anyone else experience something similar? My brother rode in the passenger seat and seems to think it might be something with the AT, as it seems to vibrate from that area. Any ideas, before I take it to Infiniti? Also, if you have a 2008, maybe you could measure the sound db at that speed and tell me how yours sounds. Thanks!

Update 5/18/17
I've noticed that the noise...which sounds like the engine revving hard with a low frequency hum...is louder when driving straight or veering left. When I veer right, on a curve, it's quieter. Would the driveshaft have this effect? Or might it be the wheel bearing?

 

Tire noise maybe?

 

Doesn't seem like tire noise.

 

I have an 08 but all of my exhaust mods would skew the results for a recording. I also vote tire noise, especially if it gets louder while going faster. If not, you could be on to something with the driveline guess. My roommates driveshaft on his G fell out of alignment or balance and caused a noise/vibration. He just turned up the music and got used to it, that was like 6 months ago.

 

Definitely not tire noise, as I can be driving 25mph and it still sounds loud. Driveline huh? It sounds and feels like it could be from there. Did your friend get it disgnosed?

 

Funny you ask, we talked about it last night in the garage. It ended up being his driveshaft/midshaft bearing or something of that nature, he had it replaced and ended up being about $600 parts and labor at an import specialist shop. The dealer will rape you for probably twice that.

 

Thx for the info! I feel that the problem is somewhere in the front, as that's where it seems to emanate from. Any chance your buddy would be able to do a sound test on his G?

 

I think I just diagnosed the problem, thx to .
Wheel bearing is bad. I have the exact sound.