Rear Suspension Overhaul
I was hearing some clunking noises from the rear of the car during shifting and occasionally when driving over bumpy roads. The suggestion from the 300zx message boards was to replace the worn out differential mount with a new polyurethane mount. At the same time, they suggested replacing all the sub-frame bushings while I had the rear of the car torn out.
The differential mount came out easily, so I assumed everything else would be the same. I planned to do the bushings one at time while the suspension remained in the car. I finally came to a couple of bolts that were rusted/seized so tight that I had no choice but to drop the whole suspension and work on the bolts out from underneath the vehicle. Ironically, the two bolts that would not budge were the bolts used to adjust the toe during an alignment.
I had to cut the exhaust in a few pieces because it wound through the rear control arms on its way to the back of the car. With easier access to those bolts, I was able to beat the **** out of them with a hammer and punch. They eventually broke free after about 30 minutes of pounding (not to mention a few whacks at my hand and thumb). I tore a rubber CV joint boot on the axle while removing the suspension from under the car, so I had to replace that also.
I cleaned up the rust off of most parts and sprayed everything with a rust converter paint. Any remaining rubber from the old bushings was removed with mapp gas and a wire wheel. I installed all the new bushings and also some new spring seats.
My brother and a friend from work helped me raise the entire thing back up into the car and bolt it into place. The car sits slightly higher now due to the new spring seats. The negative camber has improved a couple of degrees also.
I took it for a short test drive and all the noises seem to have disappeared. Its hard to tell for sure right now because the exhaust is still not repaired.
I picked up some 17″ wheels off craigslist. They’re from a Nissan 350z. I’ll be installing them in the next week or so along with some shiny new rotors.
