I am getting a noise coming from my rear diff pinion bearing after putting on said bushings. It is a howl you can hear slightly @ 40 mph and loudly @ 60mph. I followed directions to the T and torqued all bolts to manufacturer's specifications. After hearing noise and finding where it came from, I remove the bushings and the noise went with it. Anybody have any recommendations? Thanks for your time and help.

Originally posted by Imprezanator
I am getting a noise coming from my rear diff pinion bearing after putting on said bushings. It is a howl you can hear slightly @ 40 mph and loudly @ 60mph. I followed directions to the T and torqued all bolts to manufacturer's specifications. After hearing noise and finding where it came from, I remove the bushings and the noise went with it. Anybody have any recommendations? Thanks for your time and help.

I get a howl on decel in gear at around 4k RPM, but it's no big deal. Maybe try putting in just one of the two outrigger bushings on each side and see what happens.

-my 0.02

Its called NVH. The poly bushings transmit WAY more sound into the cabin that the super soft stock ones.

I have the same bushings and the same noise. I think it's just something you have to deal with. Subaru put those squishy stock bushings back there for a reason. Personally, the feel of the hardened bushings outweighs the noise.

Originally posted by markus
Its called NVH. The poly bushings transmit WAY more sound into the cabin that the super soft stock ones.

What is NVH? I undersand what is being said, I jsut do not know what that stands for.

Are the polurethane bushings really worth it. I have done the steering rack and will probably do the rear stabilizer and lateral arms next, maybe rear diff also.
Thanks

NVH= noise, vibration, harshness. It's a term used in the car-building business all the time.
BTW, I also noticed a major increase in NVH when I did my whiteline bushing install. But they solved the "big bang" on quick shifts, so they will stay in.

So even though there is noise, there is no damage being done?

NVH is a big thing. A lot of people hear noise, and it basically makes someone think "this vehicle is a piece." Depending on the noise it may be bother some or intrusive. Quite a bit of testing goes into checking each part before it is released and for a while after. SPL's, accelerometers, bonking, critical speed tests, ride and drives, strain gauging of lots of stuff...it goes on forever.

This not to say that all noise should be ignored. But when you change some thing that will transmit the noise, like when I switched to solid mounts on my old neon, and the stearing wheel stared to just vibrate, it should be expected.

Imagine how much noise and how much your car would vibrate if they put the most solid bushings/suspension (ever rode in a car with coilovers?)/really low profile tires/open exhaust/yada on your car from the factory. It would seem pretty harsh...wait a minute...Noise... Vibration... Harshness