Does anyone or any of the vendors/shops on here have a few spare diffs laying around that they can check this out for me???

I plan on calling around and seeing if my local courtesy parts or other dealers may have these parts in stock to compare at the parts counter but what i need to know is if the 3 bolt automatic diff companion flange can be removed and the 350z specific 4 bolt companion flange can be installed in its place?

I'm working on installing a 3.7 final drive diff into a friends 350z but were having a hard time finding the right diff with the 4 bolt pinion/companion flange....but we are finding tons of 3 bolt 3.7 G35 automatic sedan diffs...

REVIEW HERE IF ANYONE IS WONDERING WHAT WERE DOING:
https://my350z.com/forum/engine-and-...z-3-538-a.html



An option would be to swap flanges.....anyone have these laying around that they can check the spline count, diameter, nut thread, etc, etc...

My guess would be that it will work if a G35 4 bolt companion flange is purchased since both have the same 3.7 ratio...doubt Nissan would change the pinion spur gear and the pinion flange????

However, I'm not sure if the 350Z 4 bolt will work. since those mount on either a 3.3 or 3.5 gear set pinion/spur gear.

Any help is appreciated?

-J

 

350z 4 bolt pinion flange: ~2.56 CTC



Remove pinion/companion flange: ~ fab home made tool,lock in a vise.....something to hold the flange from spinning:


-Jason

 

I saw this over at g35driver:

http://g35driver.com/forums/drivetra...ferential.html

quotes: "The 3.7 diff now has the original 3-bolt flange attached [.]" and "...and a modified pinion shaft..."

seems to me like he had modified it before selling to hold a 4 bolt.

 

^ okay great...based on that, the a 350z or G35 3.5 4 bolt flange wont fit with out "modification".......curious now what exactly that was??? im gonna pm him this thread link...

Now, im betting buying a 4 bolt flange from a MT 3.7fd G35 sedan 2007 or 2008 will most likely simply bolt right on...

-J

 

Yes, I had to shorten the pinion shaft on the 3.7 inorder for it to mount to the drive shaft. That was the 3.7 that I got off an auto, however, it was an open diff so I replaced it with my current 3.7 that came off an 09 G37S 6MT which has a 4-bolt flange and bolted directly in place without modification.

The flanges are interchangeable.

 

It wasn't the flange that was modified, it was the shaft it slides on to. It was too long and needed to be cut since the rear portion of the drive shafts are different on some models. Below are the threads I referenced before doing the swap.

I simply removed the 4 bolt flange from my original 3.5 and installed it on the 3.7(off an auto G37), after shortening the pinion shaft everything bolted on place with no issues.

http://g35driver.com/forums/drivetra...tial-swap.html

http://g35driver.com/forums/engine-d...pkin-swap.html

 

^ okay, got it.......i figured a 3.5 4 bolt may need some modification, and that makes complete sense since they come off different gear ratio pinion/spur gears...

Now, one more question? do you know if an actual "4 bolt flange" taken off of a 3.7 MT 2007-2008 G35 sedan will slide onto an automatic 3.7 G35 diff??
-J

 

^I honestly don't know, but I would think so.

 

ya...i would think so..

okay well this helps a lot...any z owner with a 4 bolt flange diff can locate and buy a 3.7 diff from a G35 late model and swap flanges and hit the road...with a wee bit better gearing...

Finding a 3.7 auto diff is easy at junk yards and other online junk yard finder sites......i see some going for 400 quite often.

local to me in DFW, i found a local junk yard with a 3.7 auto diff off a low mileage G35 sedan auto that would work great for someone and they wanted 400 picked up...being local, i bet you can offer less.....

-J