hulksmash

i installed the whiteline rear subframe bushings last night and I'm getting a whiney noise from the rear of my vehicle. on the highway when i gas it the noise is gone. do any of you guys with this mod have the same noise.

BillJC

iTrader: (1)

It's normal. The harder bushings increase NVH of the rear subframe.

SubyGC8

I know this is an old thread but I installed mine last night. I have access to a lift because I work for a dealer. I heard the same noise and today I checked it out. Drove my car while it was on the lift. Its not normal noise! The bushings change the pinion angle in the rear diff. Your hearing the diff whinning as a effect because of the change in pinion angle. This is not good at all and will prematurly wear out the differential bearings, pinion gear, and ring gear. If you want the same performance that the bushings offer use the rear diff locking bolts, but do not leave them in for long periods of time.

Kay95

how many degrees of change would you say?

SubyGC8

I can't honestly say how many degrees. But your dropping the front of the subframe by about 7/16 of an inch while the rear of the subframe remains in its original position. The rear diff as you know is stationary so with the change in the angle of the subframe you will have a change in the angle of the diff. It is enough to cause the diff to whine. And that whine is enough to prematurly wear the ring gear, pinion gear and the pinion bearing.

Kay95

a 7/16" is a lot to drop and it sound like there are bushings missing from the set

but do you think a shim could be made and put between the subframe and the chassis?

SubyGC8

There were no missing bushings. The kit came complete. These bushings basically are shims, that go between the subframe and chassis. They are made to prevent up and down movement in the subframe under driving conditions. The factory bushing remains in the subframe since they are pressed in, and the new (bushings) are set on top and bottom of the factory bushing. And yes, a 7/16" drop in the front of the subframe is a lot. A shim could be made to raise the front of the differential up off the subfame to return the diff to its normal position but I hope you're good at geometry since its not going to be as easy as sticking a 7/16" shim in there. I dont want to scare anyone away from these bushings. They do provide a great feel, but I just wanted people to know that the whine you hear is the pinion bearing and it is not good for it.

Kay95

well how hard can it be if you know the thickness it has to be because all you have to do is take the old bushing and make it thicker

should whiteline be informed of this because i wouldnt think they want to change the pinion angle much if at all due to this wear issue

hulksmash

i checked out the bushings once again. the sound i'm getting is from the diff. it's normal. there's only like 1mm more thickness. the bushings just fills in the extra space left by the metal spacer. the noise that we're hearing is transmitted from the diff. alot goes on in the diff. so no worries guys. i had the car on the lift and had my co workers help me troubleshoot this noise.