I've got an 05 G with atx and was doing alittle reading about swapping in the 350z differential because of the gearing. I'd lime to hear alittle more from people that have done the swap.

The reason I'm wondering is because I've come across a few of them at salvage yards. I didn't ask how much they wanted. Of course they had some rust on the outside but that shouldn't matter right because everything is sealed inside. If I decide to do the swap what should I look for on the pumpkins? What's good and what's bad? How can I check to make sure everything is mechanically sound? Also, what's a good price to pay?

Is there anything I should do before the install. Is there any other part I should
add to maximize the benefits of the swap?

For those of you that have done the swap, how was your mpg effected? I've heard it's the same in city driving but on the interstate/highway you lose 2-3 mpg's. Is this right?

All in all is this a good mod for the money? The install looks fairly simple and being an auto guy, I could definitely use the benefits of better gearing.

 

I have swapped in a 3.5 so here are my thoughts. A great price would be under $300 and a decent price would be between $300-400. Are you looking for a 3.5 or 3.7? The 3.5 is a direct bolt on, and the 3.7 requires minor modification to fit. It's going to be hard to assess the functionality of a used pumpkin just by looking at it, but I would definitely spin the flanges to make sure they rotate freely and make no noise.

I don't think there's anything else you need to add for the install, it's a fairly simple swap if you have access to a lift. I personally wouldn't try it on jack stands as the pumpkin itself weighs around 100# and you have to angle it to get it out and then to get the new one in. However, I know of a couple of people that have done it at home so it's doable.

I get the same mileage around town, but lost about 2 MPG on the freeway as my RPMs have gone from 3000 at 80 MPH to 3200. IMHO it's definitely worth the money as it makes around town driving more fun as the new diff spools through the gears more quickly. However, I would expect slower 1/4 mile times as you would have to run into 4th gear at the end, most with the 3.3 that drag can push just to the top of 3rd gear at the finish line.

HTH

 

3200 @ 80 is what I got also, stock tire. Doubt the previous owner swapped it.

 

I went the other way from a coupe with 3.5 to the auto sedan 3.3. I did the swap on Jack stands in my garage with the help of a buddy. I guess one thing tonmake sure is you get one with VSLD if you spin the one side the other side should the opposite direction. VSLD was not on base models but on the brembo equipped cars for sure.

 

i didn't know about spinning the one side and the other side spin in the opposite direction. that's good to know. thank you.

did all Z's come with vsld's? i haven't found but one G but i've found multiple Z's and one differential was already off the car while the other was still mounted but the whole axle assembly was off the car. when i go back i'll check out the differential that's already off the car.

i wish i could find a brembo equipped car. i'd love those damn brakes.

 

Base model Zs didn't have VLSDs.