Album: Photos:Car:NissanRear
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My 2004 Nissan 350Z is a great car, but there are some design flaws. The rear end gets rather squirrelly at the limit of traction. Since it's not really my play car, I just lived with it, figuring it would take significant effort to fix.

Then, my rear differential bushing died, which is quite common in these cars. Nissan made that bushing very squishy and full of silicone goo. The rubber breaks and all the goo leaks out. Then there's a big clunk with every high-rev shift. It's very annoying. You can see the black streak under my old bushing where the goo leaked.

So, I went looking for a fix and found that Nissan doesn't sell that bushing (not that I want a direct replacement). Instead, they want to sell you the whole rear subframe. Going that route basically totals the car. Instead, the nice peeps at Z1 Motorsports designed a cure. (I don't normally shill for companies on my site, but they are good.) Z1 makes replacement bushing for the differential, which will fix my car relatively cheaply, and surely last way longer than the stock bushings. They also make front bushings, as mine were in bad shape. And, they make an extraction tool to remove the big thing from the subframe. How great is that?

While shopping for the bushings, I find that Z1 also makes inserts into the rear subframe bushings, firming that up as well. The reviews were all good, and the price was right, so I got those, too. Considering how noisy my Supra is, I can live with a slightly noisier 350Z, if it fixes the squirrelliness. Since fixing the differential bushings requires basically the same disassembly as adding subframe spacers, doing both at the same time makes the most sense.

Differential bushing set; Removal tool; Subframe spacer set

I knew this would be a big job, even though the reviews and description said it would not take more than about 6 hours. It took me two days, but I had to deal with rusty fasteners. Also, it took me an hour of cranking to get the old subframe bushing out. That was quite a workout! My lats and delts were sore after that workout.

In case anyone happens to be reading this prior to tackling the job, one trick is to put the new rear polyurethane bushing in the freezer overnight before installing it. That will shrink it a little bit, making it much easier to tap into the subframe. Also, I coated everything with silicone grease (aka dielectric grease) before installing. That allowed everything to slide together nicely.

This is a smattering of photos, not meant to be a complete chronology. Z1 describes the problem completely, and there are videos on the Web that show the whole process.

After driving the car regularly, it's a very different car, really what it should have been from Nissan. The understeer is just about gone and the whole car is very behaved with no vagueness like there was before. There is definitely more noise from the rear, especially on the highway, but it's mild. The extra noise is definitely worth the trade for way better handling. Shifting smoothly is so much easier now with the differential bushing upgrade. I should have done this years ago.

Rear subframe bushing Front subframe bushing Rear with new insert Rear other side
Rear upper insert Dangling subframe Front upper insert Other side front upper
Stock front diffy bushings removed Dead rear diff bushing cored Stock rear bushing is out! New one installed
View of the front Diffy installed! View of the rear
All photos Copyright Brian A. Whaley. All rights reserved.
Album created by album tool from D. Madison's MarginalHacks on Sun Apr 4 09:59:15 2021