I have an '03 5AT G35 Sedan which I bought new in July of 2002. I also own a Quaife Differential. I have yet to have my Quaife installation completed, as a fitment issue became apparent on my local Infiniti dealer's first attempt so to do.

It seems there are two stock differentials on the G35: one for the 5AT and another for the 6MT. The Quaife was designed to replace my 5AT differential 1-for-1, a straight bolt-on installation. For those with a 6MT, I understand a custom 10 mm spacer must be attached to the Quaife's ring gear shelf to allow for proper alignment/fitment inside the pumpkin. Longer screws are required as a result.

Much to my dismay, despite the fact I have a 5AT, the Quaife doesn't fit! It's off by 10 mm. It seems as though my 5AT equipped G35 Sedan was shipped from the factory with a 6MT differential. Can this be?

Any informed feedback would be much appreciated. Thanks.

 

That's very interesting! I know we fitted one into a 03.0 5AT diff. without any problems.

You should be recieving the spacer and extended bolts from Quaife either way (free of charge). Let us know how it goes.

 

Hello, Clint. I'm glad to hear your install went OK.

Unfortunately, that does not shed any light on my fitment issue. It's very strange that I had a problem at all. I was somewhat taken aback by this finding, and so was Sharif, my installer, and at least another 1/2-dozen other folks. I have been asked repeatedly if I've ever swapped my stock diff for another. I've been asked if I'm sure I bought the car new.

I bought the car brand new, right off the lot, in July of 2002. I have never swapped diffs, nor trannies, nor pumpkins, nor any other drive-line components. (I never even tried until I bought the new Quaife.) Nobody can understand why my new Quaife will not directly replace my stock 5AT differential as it was designed so to do. The ring gear shelf on the Quaife is off by 10 mm, but it should be spot on. The new fitment kit should do the trick, but... Who knew?

I wonder if my FD is a 3.5...? I'll find out when my diff goes back under the knife in a few days or so, once I receive the new fitment kit. I'll ask my installer to take lots of pics, and I'll advise the outcome as soon as possible. I can't wait to have it installed.

Take care.