Gregor12

iTrader: (3)

Hello guys and gals, I decided that I wanted to tackle this upgrade for my sedan. I've read a lot of different information over the past year and never found concrete information about this modification so I decided to post here to help out the other members. I found some time over the holidays to finally install the diff that has been sitting in my garage for 4 months lol. I also replaced the factory differential bushings with the whiteline differential bushing set. I used a DIY thread on here to complete the bushing install and it was by far the hardest part of this "adventure". So here's the deal on the diff upgrade. THIS IS THE EASIEST WAY TO COMPLETE THIS UPGRADE. I'm not a pro and I am not responsible for anything that happens to you from following this thread. Wouldn't really say this is just a DIY but I did it more for a review and to help other people that are interested in the mod. I only added the steps to give everyone an idea of what you must do to swap diffs. Kinda helps decide whether you want to tackle it or not. IMO it was a royal pain in the *** to do it on jack stands. Anyways, here it goes.

-Donor car must be a 2008 Infiniti G37s coupe AT for the diff to bolt straight in (not sure about the sedan. But if someone gives me the measurements from the diff flange to diff cover and checks if it's a 3 bolt or 4 bolt flange then I'll let you know if it's the same)
-Must buy nuts, bolts, and washers to bolt your factory axles to the new diff as the stub axle holes in the VLSD are NOT threaded like the open diff that came with your car from factory. The bolts and nuts are from a 350z so order from Nissan. Some years have threaded axle holes but my g37 (2012) has the threaded stub axle holes. if your axles are threaded then you can reuse the stock bolts. If you choose the same path that i went then youll need to order these:
Part numbers:
3960622P0A (Qty:12)
3960703P0A (Qty:12)
Random 10mm lock washers from lowes or something

I did this in my garage on jack stands alone so it can be done without a lift, just be careful as the diff is heavy as heck. Here are the steps I took.

-jack up the vehicle leaving you plenty of room to work. You'll need a spare jack or something to lower and hold the diff as you unbolt it.

-Remove all of these things in the following order:
1. Axle back and mid-pipe
2. Exhaust heat shield covering the driveshaft:diff bolts 4 10mm bolts. Another guy on here removed both and that will make it easier but I got it out with on one shield removed as the drive shaft does have some play.
3. Rear away bar
4. Remove the three 17mm bolts holding the drive shaft and differential flange together (put something there to hold the drive shaft up. Don't let it hang)
5. Remove all 12 14mm bolts that mate the axles to the diff (I recommend zip-tying the axles to the lower control arms before Unbolting. Don't let them just hang)
6. Remove both speed sensors on the Back of the diff (12mm bolts)
7. Remove the upper ventilation tube for the diff as well. Here's the vent tube since it's hard to see it from the bottoms


Now that the diff has been freed of everything you need to drop it out of the car.
8. Start buy breaking the two front mount bolts and the rear mount bolt loose. (All 15mm)
9. Place your hoist or jack underneath the diff to support it and remove the 3 bolts carefully. The diff will not come straight down. You must bring it forward by about an inch to remove the back stud from the subframe and then drop it straight down. Be very careful with this step as the diff is extremely heavy.

This is what it should look like now


If you're doing bushings as well (which I highly recommend) you want to carry out this process next. Here's a DIY that I found on here:
https://www.myg37.com/forums/d-i-y-i...-bushings.html

After you've finished the bushings it's time to install the new diff. Just follow the steps backwards and you'll be done. Don't forget to order the bolts and nuts that I posted above. Or you'll be stuck with your car on jack stands for 4 days like me.


REVIEW: I feel like this is a huge bang for the buck!! The car just feels way better under normal driving and under hard acceleration. Driving around the city and accelerating from a stop is much easier. The car doesn't seem sluggish any more and it takes a lot less throttle to accelerate. Whenever the car breaks traction it's much more stable as well. It just kinda slid and kept accelerating in a straight line smoothly. I've recorded MPH and RPMS from the old diff and will update what the RPMS are now at the same MPH. I'm not sure if this throws off the speedometer. Not sure where the speedometer takes its reading from. I'm hoping its from the speed sensors on the diff that reads the axle speed. I will keep updating as time goes on. Feel free to ask any questions.

----MPH--vs--RPM----
----3.36 FD--3.69 FD
60---2000 --- 2200
70---2300 --- 2500
75---2500 --- 2750
80---2650 --- 2950

----COST----
$200 - Rear differential
$150 - shipping for diff
$100 - Rear diff bushings (whiteline)
$40 - Nissan 350z Bolts and nuts

$500 - total! IMO this is a huge bang for the buck. car pulls harder, gets better traction, feels more solid, and most importantly... IT SLIDES lol


PLEASE ADD IF YOU HAVE CONCRETE INFO ON OTHER DIFFS THAT ARE THE SAME. I think the 2007-2008 auto sedan also has the same flange and same final drive. But be careful, Ive read where people have had to order half of the coupe drive shaft and other things. I would stick with 2007-2008 year models for the 3.69

Gregor12

iTrader: (3)

Cruise control still works. Read online where someone said you might lose it?

blnewt

iTrader: (13)

Nice writeup, thanks for putting this together G!

Gregor12

iTrader: (3)

Thanks, and No problem man. Hopefully it's helpful haha

Gregor12

iTrader: (3)

bump for an update. forgot to add the price...
$200 - Rear differential
$150 - shipping for diff
$100 - Rear diff bushings (whiteline)
$40 - Nissan 350z Bolts and nuts

$500 - total! IMO this is a huge bang for the buck. car pulls harder, gets better traction, feels more solid, and most importantly... IT SLIDES lol

esesnipey94

Dope write up man. My boy just bought his diff & reported that the axle flanges aren't threaded like our factory one so I started to freak out since I'm about to order my diff too. But those part numbers really came through. I appreciate it. The 08 coupe s with 5 speed auto is only diff that would direct swap like this by tha way. Only other way is to do a flange replacement from the other auto or manual transmissions.

Gregor12

iTrader: (3)

Yessir! That's what I wrote originally but I saw where someone mentioned the 2007-2008 g35 sedan (vq35hr) also had the same exact vlsd in it with the 3 bolt flange. They had the 5 speed still so the gear ratio was a 3.69 as well. But until I get measurements from someone I don't want to say it's a match for sure.

As for the non-threaded stub axles, I **** a brick when I went to bolt up my axles lmao. But luckily after a lot of random google searching I saw that the 350z had neither of the holes threaded. The fit like a glove too so you'll be good. That's the main reason I posted this! Be sure to add a review when y'all are done!

RickyBobby

Ok so what cars have VLSD and which are open diff? I thought at least all G37-S had VLSD but sounds like you had to do work to get that? Mine is a 09 G37S coupe with 6MT, so I'm pretty sure mine does in fact have VLSD but can anyone clarify which G's don't so I don't get confused?

Some BMW guy was givin me **** for having open diff so I thought he was a complete pompous idiot throwing around those accusations although maybe he just made the assumption that mine might have?

Gregor12

iTrader: (3)

Your friend is an idiot... Lol jk but All S models have the VLSD option. My g37 is a base. So now with the diff I'm 1/3 S

The only reason I had to do work to get this certain diff is because i was looking for the 3.69 final drive ratio and I wanted it to fit. There was only one year that would make the swap easy, the 2008 g37s with the 5AT.

infamouslkv

Is your G sedan rwd or awd?

Gregor12

iTrader: (3)

Rwd. If it was all wheel then I couldn't swap just the rear. Having separate ratios would **** your car up! You want all the ratios to be equal so the entire drivetrain turns as one!!

Gregor12

iTrader: (3)

Bump. Everything's still going well. Lots of hard miles on the diff haha no sound or vibrations from the bushings

Baadnewsburr

iTrader: (3)

I cant emphasize how helpful this is. I'm working on a pumpkin swap myself but I can only do work on my car on very specific days and need the car as my Daily driver in between.

The worst thing is tearing down something this involved and realizing you have to wait for parts for days.

As a side note, the total for these bolts is $149.16 up here in Canada. Frickin crazy.

Gregor12

iTrader: (3)

Holy **** man!! That's insane!!! And I'm glad I could help out man! Did you try eBay to see if any vendors on there ship to Canada? Probably a lot cheaper. I think they were like 40 dollars here from Nissan.

Baadnewsburr

iTrader: (3)

I know right?...I think a lot of the Canadians on here feel my pain.

Luckily I only live an hour from the border and use a drop shipper and buy whatever I want as though I'm buying locall yor go to the Nissan/Infiniti dealer in Buffalo NY, but I always check locally first...sometimes (I.e. this time) its just for a laugh and to SMH