I have a 2011 g37x with 71k miles on it and a few weeks ago I started hearing a humming noise above 40mph. I thought it was a bad front wheel bearing so I took it to a shop and they told me that it was coming from the rear, most likely the diff. I changed out the diff fluid, the drain plug had a lot of metal shavings on it, but the noise is still there albeit not as loud. I checked to see if there was any play in the rear wheels to make sure its not a rear wheel bearing and they checked out fine.

My question is how can I absolutely make sure it is the rear diff before I drop a whole bunch of money on a new diff? And does anyone know where I can find a used diff?

 

If they can hear it, it's probably that. But that def sucks to happen just 1k miles past the powertrain warranty. How good is your relationship with the dealer?

If you need used, will this work? Used - 2011 INFINITI INFINITI G37 - Carrier Assembly - Weber Brothers Auto

 

DAMN IT! I didn't even think of checking the warranty. I would have brought it in when it first started, damn.

 

I don't necessarily have an answer for the posted question, in fact I too have a question to post. I am trying to find out what type transmission and differential fluids do I use in my 2013 Infiniti G37 S

 

Do you not have the owner's manual?