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I think the final drive gear ratio is slightly different with the X and so is the mounting flange so I doubt you can do a direct swap. But I've seem a thread in 350z where they replaced the flange. It should be "possible" but the final drive in the rear would spin faster than the front so that might cause problems to the AWD system.
Hi guys, I registered because I saw this post and have been asking a similar question for a while now. I own a 2008 G35X AWD (which have noticable similarities to the G37X) and I'm currently swapping a 1.5 way Tomei into my stock rear differential. If I can offer some advice: don't do the full teardown and rebuild without the proper tools... I learned this the hard way, the pinion bearings took forever to get in there. I'll keep everyone posted and let you guys know if it works out well or not. I reused the stock pinion and ring gears so I wouldn't end up with one set of tires going faster than the other, a burned out / broken transfer case, or whatever other maladies come with an imbalanced setup. Now I'm hoping I did everything correctly and the cars VDC / ABS systems don't go crazy.
*which have noticeable similarities to the G37X sedan.
I almost forgot to mention something: if it's an open differential, I wouldn't even trust it with a shift kit and decent tires. My pinion / spider gears' tips began blowing apart because of shock loading caused by really hard shifts (it would chirp the tires between gears while accelerating from a stop, 1-2, 2-3, and sometimes 3-4). I could almost see the same damage eventually happening with an FI vehicle, but more factors are involved. Jeff, I'd bet your intuition is correct.
Here are pics of the differential pinion / spider gears after having a shift kit for about a year. I'm lucky to have caught it before something worse happened.
My apologies for the crappy night time pic. I'll try to edit in a better one later.
Ok, so it's in there and I've been driving it around. During the latter part of break-in (not the dizzying 30 minute figure 8, but the ~70 miles afterwards where I can't go above 37mph) I've only set off the slip light for a split second (maybe 0.25 seconds) a few times. I'm about 30 miles in as of tonight.
The good news so far:
It works!!! ...so far and at low speeds with my TransGo shift kit removed (I'll likely re-introduce it later on). Even with the tiny amount of slip on rare occasion, the ABS and VDC have been completely quiet and have caused no trouble. The car now grips the road like a tank.
The potentially not so good news to date:
This is a pretty quiet cLSD (compared to a Detroit Locker in a Moser 9" rear that I saw on YouTube), but it makes noises under light to moderate acceleration around nearly anything resembling a left or right turn and randomly chooses when to and when not to do it. Now of course it doesn't sound like a "can of marbles" or "bra, your sh*t's broken", but remember it is a 1.5 Way and not a 2 Way. 2 Way cLSDs are usually a little bit "noisier" from what I hear. As I understand it, this might go away after an oil change and some time or it might be a permanent thing.
I'll log an update soon. Maybe I can post a before and after noise video (if it goes away). If not, I might have to "adjust" or add / remove clutch plates to make my LSD's locking action less eager and aggressive.
Once all is ready, I'll try putting in some time tearing *** around (semi) empty highways with a GoPro to make sure everything else works well.
If it rains soon I should also be able to test out the VDC / ABS responses to slip and other things.
The cheapest way would be to buy the Tomei 1.5 Way Differential (I wouldn't trust a 2 Way on an X just yet, it might be too aggressive for the VDC / ABS), the bearings, and some extra Tomei Fluid for after the break in.
As of late 2016;
Tomei 1.5 Way - $851 (Amazon)
Bearings - $160 (for 2 at the dealer)
Extra Tomei Fluid - $50 (Z1 or Amazon)
TOTAL - ~$1,061
Now the way I went was part out of necessity and part trying to make everything "new" again (perfectionist bs). I wouldn't advise this to anyone unless they have a fully equipped shop, differential / transmission tools, large presses, torches, paint booth, etc. I bought everything Incould think of, but it held up my daily driver for 2 weeks.
Here's the list and prices:
RE5R05A Automatic Transmission (5 Speed for the G35X, mine was failing and I got lucky with a 40K mile setup for cheap) with Transfer Case - $800
Fluids - ~$230 (Castrol initially because junkyards store parts dry, and RedLine for post-flush / permanent)
R200 differential from a local junkyard (this is a G35 rearend. The G37 might be slightly different externally, have a different gear ratio, and cost a little bit more. Research must be done) - $150
Tomei 1.5 Way (Amazon) - $851
Extra Tomei Fluid - $50 (Z1 or Amazon)
Z1 Motorsports Finned, Extra Capacity Differential Cover (Z1 or Concept Z, both carry it) - ~$180
4 2.5 Gallon containers of Purple Power degreaser (Pep Boys) - ~$70
4 Gallons of Evapo-Rust (Menards or Home Depot) - ~$95
Differential Bearing / Rebuild Kit (Z1 Motorsports) (much cheaper than the dealership) - ~$300
6 - 7 cans of Brake Parts Cleaner - ~$35 - $50 (cheapest at Menards or Walmart)
1 can of Dupli-Color Prep Spray (Pep Boys or O'Reilly's) - ~$7
1 can of black VHT Epoxy Paint (Pep Boys, O'Reilly's, AutoZone) - ~$7
Harbor Freight Degreasing Station and Sandblaster, a 10CFM air compressor (Home Depot, Menards, etc.), and 25 - 30 lbs. 180 - 220 Grit Silicon Carbide blast media (Grainger, Internet, etc.) - PRICELESS
TOTAL - ~$2,775 (not counting the undercarriage supplies and larger equipment) but it looks and runs like a champ, minus the clicking.
DISCLAIMER - most of the above was only done because I had installed a shift kit and beat on it for about a year and a half with some sticky all season tires. A buddy and I also de-rusted nearly everything and coated the undercarriage because a crappy exhaust I had was leaking condensation / water all over the undercarriage and rusted much of it. I would not advise performing this amount of work on a dd to anyone unless they're in a similar situation. Going without a car that long just sucks and rental fees pile up quickly.
Now here is what I recommend to others who don't have the issues I had:
If you have under 100k miles and your vehicle has not began it's journey into becoming a rust bucket (that happened in part because I have an '08 and part because I had went to a crappy muffler shop that didn't weld the exhaust all the way around. Since then, Infiniti has fixed many of the parts which were prone to rust like the subframe and crossmember), purchase the list below for a complete yet easy enough job:
Tomei 1.5 Way - $851 (Amazon)
Left and Right Differential Bearings - ~$160 (for 2 at the dealer)
Extra Tomei Fluid - $50 (Z1 or Amazon)
Z1 Motorsports Finned, Extra Capacity Differential Cover (Z1 or Concept Z, both carry it) - ~$180
Nissan gasket maker, HondaBond HT, Mercedes gasket maker, Permatex Aviation Gasket Maker, etc. (whichever you prefer (all are REALLY good), just be careful if using Aviation Gasket Maker as it's a pain to remove and stays sticky for a long time but doesn't really harden. If using it, have a paper towel roll and lacquer thinner nearby for cleanup around edges) - $17 to $60
Left and Right Differential Axle Stub Seals (Dealership) - ~$40 for both (be very careful tapping these back in, use a small round, flat end punch on the outer ring and only insert them so they're flush with the casing)
TOTAL - ~$1,316
Last edited by G35XS; 09-24-2016 at 02:38 PM.
Reason: Small errors
Minimum: about $1,061 (you can save some more money by reusing the differential bearings, just be careful removing them from the old diff and installing them on the new one, don't damage them. It's also a good idea to clean them up, as this differential does not like contaminants)
Going crazy like the car is going to Mecum: $2,775 or more
Buying one already built with a 1.5 Way inside: $3,000+ from Z1 Motorsports, but it's perfect and fits right in
Doing it by yourself, the right way, just without going nuts: about $1,316
Last edited by G35XS; 09-24-2016 at 02:25 PM.
Reason: Had to add info
One would think so, but I have another disclaimer... DON'T add this mod unless you pick the correct LSD for the car, it's purpose / your driving style, and your regions weather.
Tomei's Clutch LSD is far too aggressive to allow the rear slip sensors to detect slip. This is great for, and pretty damn safe at high speeds (think highway, top speed, drag, and roadcourse), but I was able to drift the car on a highway entrance at just over 20mph while it was raining. This likely means there is no slip detected in the rear wheels, so there is no correction.
From what I have been able to observe to date, during snow days this car will be a beast traveling in a straight line, but it will be horrible around lower speed and / or tighter corners / turns. All because Tomei's differential is nearly as aggressive as a Detroit Locker.
A word of advice, don't buy things just because they are a few hundred dollars cheaper and don't buy a super aggressive Clutch LSD for this car unless you live in California, Texas, or similar "dry / warm states" and actually want a cross between an expensive drift missile and a dragster or highway racer at the touch of a button (with very little safety around tight corners).
Since I'm already knee deep in this experiment cash wise, I might as well try a few other things and let you guys know. This way forum users will have a list of options they can install and the effects each option will have on VDC and ATTESA-ETS systems. I believe a factory cLSD insert from an 80's 300ZX would be perfect for this car (so long as it fits. It is highly adjustable. Both are R200 format, but we'll see), as it's much less aggressive and should allow enough slip at low speeds for the rear sensors to catch it and VDC, etc. to work.
That aside, a Torsen might be a more sound, streetable option as it biases the torque from one wheel to another under acceleration and remains open during deceleration.
I'll also look into vLSD or Viscous LSD models and call Z1 (and a local rebuild shop or two) so I see if the Tomei unit can have it's breakaway torque adjusted outside of what the manufacturer says (Tomei gives two choices: aggressive, and "brahyoushouldaboughtalockerorweldeddiff" stupid aggressive). There really is no light or medium with this LSD and it still feels like a locker, and I followed the break-in procedure to the T.
01-28-2014, 11:38 PM
