Ivoidwarranties

iTrader: (7)

I was going to look into this when I have more time, but do you know if the 370Zs use a three fingered flange on the autos for sure?

SharpByCoop

I just searched, and no, they don't. Four-bolt flange for the auto.

So it appears the G37 (G35?) autos are the only ones with the three-finger rubber coupling instead of the U-joints.

That limits the amount of 4.08 drivers.

Coop

jujubii

iTrader: (5)

hey coop,
just wondering if you checked out custom cf driveshaft group buy thread. it seems to be popular and has recently been gaining traction. maybe the company there can make one for you?

TVPostSound

iTrader: (9)

Think about it, the pin locks the shaft to the pinion flange, locking them together angularly, The rubber coupler only absorbs rotational shock.

By losing the pin you have induced universal action, thus your vibration.

Her's what Corvette owners do:

Six Shooter Driveshaft Couplers - Coupler Therapy - Vette Magazine

Ivoidwarranties

iTrader: (7)

That's what I thought. I think you should get rid of the three fingered flange, put the manual flange on and get a custom driveshaft made that replaces your stock unit. And then have them make another one so I can buy it and do this mod. Serious.


Nice bit of info. But even using something like this, wouldn't that be the same (universal action because of losing the pin)?

Ivoidwarranties

iTrader: (7)

Thinking out loud again... You know, when we swapped rearends in the 300C SRT8 to an upgraded Getrag, we had to switch over to a different drive shaft because the input flange was different on the rearends. But if I remember correctly, we had to use the front half of the stock drive shaft because it mated to the transmission correctly and we had to use the back half of the new drive shaft because it fit the new Getrag rearend. These were two piece shafts that had the same type of middle connecting joints.

I wonder if the back half of a drive shaft from a manual Coupe would fit? How cool would that be?

indyn

Coop,
When Z1 were selling Aluminium driveshafts, they sent me a manual driveshaft for my automatic car, it was a mistake of course, but the lenght of the manual and automatic driveshafts were same except that the pinion shafts are different.
So if you already got the manual VLSD installed then why not just get a manual driveshaft instead of changing the pinion shafts, this might be a easier route, no?

SharpByCoop

^^^ Yes. If I were to stick with an OEM driveshaft, this would be the answer. Or, simply change the nose from the manual.

Great idea. Can you clarify: Is the nose for the manual trans the same as the nose for the auto? We know the three-finger rear flange is different.

I even thought about using a 'spacer' for an OEM 350Z one-piece shaft. However it would have to be an 8" spacer. That's how much longer the G's wheelbase is. (The 370Z is 12" shorter!) NFG.

I sent a query to Sam @ GTM. I know of the CF thread, I'm on it. However, I'd rather deal/support with someone who knows how these combos fit, rather than save a few hundred in a deal.

Coop

indyn

if you mean the other end of the shaft, they're same. But here are some ebay listings for auto and manual driveshafts.

http://www.ebay.com/itm/08-09-10-11-INFINITI-G37-COUPE-OEM-FACTORY-AUTOMATIC-DRIVE-SHAFT-G37S-VQ37-/271024665998?_trksid=p2047675.m1850&_trkparms=aid%3D222001%26algo%3DSIC.CURRENT%26ao%3D1%26asc%3D11%26meid%3D7051434981490684590%26pid%3D100011%26prg%3D1005%26rk%3D3%26sd%3D370758898122%26

2008 Infiniti G37 Coupe Sport Drive Shaft Assembly VQ37 27K | eBay

Kojack

iTrader: (2)

sharpbycoop- i tried to do a search but couldn't find it... any reason why you couldn't just get the nissan 4.08 gear and install to your diff?

SharpByCoop

OK. So If I'm reading this correct the ONLY distinction between the auto driveshaft and the manual is the rear flange. The front nose from a manual will slip into my auto. Says you.

This said, If I 'simply' got a manual driveshaft and reconverted back to the manual diff flange, I'd be set with proper support. Either an OEM 2-piece or a CF 1-piece.

I completely don't understand your comment clarify? I have the 4.08 Nissan gear, and they ONLY make this for anything BUT the auto.

Next post I have a comment....

Coop

SharpByCoop

I was just thinking about this change and recognizing that ALL of this is irrelevant to anything but a 2008 Infiniti 2wd auto.

You see only in 2008 did the 5AT have a 3.69:1 ratio. For me a 12% increase in gearing needs to go to the 4.08 gears. And... it's a great change.

This said, the 2009-2013 autos have a 7AT with a 3.35:1 rear ratio. Same driveshaft, same pinion extension.

if you were to increase a 7AT to the same degree as I wanted, you would only need to go to a 3.69:1 ratio (12% increase), and that's available from Infiniti, includes the support pinion, and doesn't need a manual differential to fit.

Why pay more?

Going a step further, I read the G37 convertible has an OEM ratio of 3.91:1. And we know they make autos for the convertible, too. Same driveshaft, same pinion support? I'm ASSuming.

I could have eliminated ALL of this if I ordered the convertible OEM gearset and installed it in my existing diff. But, for only an increase of about 6%.

That's what I'm seeing.

Coop

Black Betty

iTrader: (60)

Coop I have an OEM 6MT drive shaft out of my car and I have taken all the critical measurements. If you measure yours and find that everything is exactly the same between the MT and AT except the coupling, couldn't you simply use an MT drive shaft and differential pinion shaft? Basically convert all your AT hardware to MT hardware?

SharpByCoop

^^^ Yes. That's what I'm thinking.

I assume you meant to say pinion flange, not shaft.

Getting these measurements would be easy on a lift. Not so easy in my driveway. LOL!

I'll see what we can do. Did you replace yours w/alum?

Coop

Black Betty

iTrader: (60)

Yes, I meant the pinion flange not shaft.

The shaft would need to be removed from the car to measure it properly. Taking it out is extremely easy, 20-30 minute job tops. I took mine lying out on my back in the driveway and I am not a small man. I have all the measurements you'll need because I provided them all to the shop that made the CF shaft in the group buy thread. Let me know if you want me to PM them to you.

Looking at the photo of the AT shaft on eBay, it appears to be the same as mine except for the flange. Only precise measurement will tell for sure but it might make your life a lot easier to find out.

Yes, I replaced mine with the Z1 aluminum 1 piece shaft.