M35x Rear Differential

[bmiller79]

Hello fellow Infiniti/Nissan enthusiasts,

I am new to the forum. This seems to be the best place for information when you own a Nissan or Infiniti. I have a 2006 Infiniti M35x. It has 151,000 miles on it, and i just bought it in April 2012. I truly love this car. Too the point though...

It has been making a noise which increases the faster I go. You can't really hear it until you reach over 45 mph. I initially thought it might be a tire out of balance, so I had all of my tires rotated and balanced and the noise still persisted. I finally took her to the Infiniti dealership yesterday and they told me my rear differential had no fluid, and that it appeared that it all leaked out of the main seal (pinion seal?) at some point, and they advised that the differential would have to be replaced because it likely had been irreversibly damaged. They added fluid, and send me on my way with a few quotes which started at $1400. I thought maybe the fluid would make a difference, but it didn't The noise is quieter, but it is still there. It also has begun visibly leaking fluid now, so they were correct about where the fluid was leaking from.

That total is enough to make me want to try to fix this myself. I have located a rear diff. from a 2007 M35x. Does anyone know if this is compatible with my 2006? Any other information or advice would be appreciated.

Brock

[EniGmA1987]

I am 90% sure a 2007 M35x rear differential is compatible with the 2006 M35x. They are supposed to be the same car for those years, it was in 2008 that there was an update. If you didnt have a x model then you could even pull a G35 rear diff from some years and a g37 differential from a single year it had a 5 speed trans.

The only thing that would make the 2007 incompatible is if Infiniti decided to change the spline count between years, which there is absolutely no reason to do so and would just be weird. So it should work out.