3.9 fd on automatic
 

i know doing this envolves swaping the for the m/t pumpkin w/ 3.5s and then having the 3.9s installed; rather then trading assemblys with someone is it possible to just buy a new one from nissan? im looking to gear my 07 auto and im not really sure where to start

Your best bet would be to look in the classifieds. Every now and then someone is selling a full pumpkin with a 3.9FD and stock lsd or better. Someone who has a TT may even want to trade for your pumpkin.

you would have to buy a full 3.5 equipped pumpkin from Nissan, which is around $1600 IIRC. Best bet is the private classifieds

Classifieds or a junkyard. I bought my assembly used for $250 from a G35 6MT sedan owner who had swapped his out with another assembly that had VLSD. What I saved pretty much covered the cost of the Quaife diff I bought.

I'd recommend checking this thread out since you're in NJ.
https://my350z.com/forum/north-east/370735-feeler-on-a-lot-of-quality-parts.html

Where did you hear that you had to have the manual tranny pumpkin? Performance Nissan sells the 3.7 or 3.9 gears and they have the list of items that needs to be changed - lots cheaper then the whole pumpkin. But if you must change pumpkins why not buy the G37 coupe one from infiniti as it comes with the 3.69 gears already there. All of this is from researching sites and sponsor links and making a couple of calls. Now all I need is the money to do it.

you're not speaking the to the correct people in all honesty

To do a 3.9 into a auto, you need a manual transmission pumpkin. This is separate and apart from the install parts that are needed (these install parts are needed no matter what transmission you have). The reason is because an automatic and manual use a different diameter ring gear, and a different differential as well.

The other option that might work (I cant say for sure as I've never done it) is to use an auto pumpkin with manual trans differential and 3.9 final drive. I don't know if the pumpkins are physically the same though so it would need to be researched more thoroughly

Its actually how mine was done. We had an issue because the companion flange was changed on the 04.5+ diffs so I couldn't use the 03 carrier on my 05 as a base for the rebuild. Ended up using the 05 pumpkin, flanges from the 03 and a couple other items, combined with the rebuild parts, 3.917 ring and pinion and the quaife.

Takes a lot more work though as its a 100% internal rebuild, and probably not what I would recommend if you can avoid it.
https://my350z.com/forum/engine-and-drivetrain/208582-people-who-have-swapped-pumpkins-please-chime-in.html

good info...some STICKY THIS! I figured it wouldn't be the easiest route to go

Interesting. I was under the impressions that the AT & MT housings were different and this wouldnt work.


+1

The housings are the same, or at least similar enough to make it work. They're only slightly different between R200V and R200 which signifies VLSD or open differential. Its the only difference indicated that I've come across.

I'm coming in close to 20k miles on my setup and it's still as smooth as the day it went in. Forget exactly how many miles I was at when I had when it was done, but it'll be 2 years in August.

so, nobody makes a ring & pinion swap kit for the A/T? i would have to run a M/T diff?

bump

Yes you need a diff designed for the 3.538.

What section of classifieds