Weird noise from the rear - no where near stock setup
07-30-2010, 06:00 PM
#1
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Weird noise from the rear - no where near stock setup I've got a Strange 12 bolt out back with complete rod end suspension, the torque arm, the panhard bar, and LCAs. The sway bar is a beefier unit, not sure of the size nor brand with Energy Suspension stock length end links.
Whenever I am making left turns into or out of funky drive ways, I get a clunk from the rear. Everything seems tight and there is nothing in the left rear quarter to make me thing is loose. The spare, jack, and fasteners are removed and I am pretty sure it is coming from the left rear. Sometimes the noise is worse than others and if I creep slowly, sometimes it won't make a noise at all.
To just drive slow isn't always ideal as sometimes I am pulling off of high traffic roads with 45-60+ MPH speed limits and don't need to get rear-ended and total the TA.
A little background, last November I was cruising along doing 40-45 MPH when a car headed the other direction pulls right out in front of me. That car was sitting and waiting for as long as it was in my sight range. I cut right HARD and it is only a (2) lane road in each direction and had to cut back left quick. I cut too much and ended up doing a 180 and flying sideways across the curbed median @ 35+ MPH. Other car took off and a few months later I begin to notice this noise.
Now, where the panhard meets the upper rear subframe, it appears as if the bolt's washers have scraped across the mounting plate for the PH bar. The plate is black and the scratches are obvious as they are starting to surface rust over. My axle may be a little off-center, but I notice no other driveability issues and the car dead hooks in 1st on the street with Nittos.
I have read that my sway bar may be rubbing the rear diff cover, I will check that tonight as I am swapping rear gear lube. This problem seems to occur when the left rear tire is compressed into the wheel well and the right rear hangs low, putting something at a funky geometry giving me this noise.
Sorry, for the long read, but does anyone have a similar suspension setup and been in this situation before?
Whenever I am making left turns into or out of funky drive ways, I get a clunk from the rear. Everything seems tight and there is nothing in the left rear quarter to make me thing is loose. The spare, jack, and fasteners are removed and I am pretty sure it is coming from the left rear. Sometimes the noise is worse than others and if I creep slowly, sometimes it won't make a noise at all.
To just drive slow isn't always ideal as sometimes I am pulling off of high traffic roads with 45-60+ MPH speed limits and don't need to get rear-ended and total the TA.
A little background, last November I was cruising along doing 40-45 MPH when a car headed the other direction pulls right out in front of me. That car was sitting and waiting for as long as it was in my sight range. I cut right HARD and it is only a (2) lane road in each direction and had to cut back left quick. I cut too much and ended up doing a 180 and flying sideways across the curbed median @ 35+ MPH. Other car took off and a few months later I begin to notice this noise.
Now, where the panhard meets the upper rear subframe, it appears as if the bolt's washers have scraped across the mounting plate for the PH bar. The plate is black and the scratches are obvious as they are starting to surface rust over. My axle may be a little off-center, but I notice no other driveability issues and the car dead hooks in 1st on the street with Nittos.
I have read that my sway bar may be rubbing the rear diff cover, I will check that tonight as I am swapping rear gear lube. This problem seems to occur when the left rear tire is compressed into the wheel well and the right rear hangs low, putting something at a funky geometry giving me this noise.
Sorry, for the long read, but does anyone have a similar suspension setup and been in this situation before?
07-31-2010, 10:22 PM
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I looked underneath as I replaced the rear diff gasket and fluid. The only thing I noticed was a small polished section on the top of the diff cover. It appears as it is rubbing the gas tank when the rear squats. I already have a DA spherical rod ended PH bar. I guess I just need to drop a bob and check if it is centered.
08-04-2010, 07:53 AM
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Here are some things I found last night.
You can see the small polished part on the top of the diff cover. I do not think this is the major contributor.
Here is where it is hitting the tank. I think this is more from squatting under hard acceleration more than anything. I don't think this makes enough contact/restriction to cause the loud pop I can occasionally hear.
This is the upper PH bar bracket. I think this was moved from flying over the curb about a year ago. Since the marks are rusting over, I don't think it is moving at all, but may need to be adjusted to get it back on center.
This is the driver side rear bump stop. Looks to have roughly a 1/4" of clearance with the 315 Nittos.
This is the passenger side bump stop. It is making contact with the midpoint of the sidewall. Since these are 315s on a 9.5" wheel, it flares a little bit towards the tread. The tire didn't appear to have any major scuff marks that you would think this kind of contact would make, much less at speed.
Keep in mind, all of these pictures are at full droop. With it being at full droop, and just eyeballing it, the rear end seems to sway about 1" towards the driver side. Since this is a PH setup, I know it has a small arc as it travels through its range of vertical motion, but I do not know a standard distance or specifications. I will have to drop a bob at compressed high and see where it is. I am also going to raise it up tonight and support via the rear end versus the subframe to check that mount at ride height.
Let me know what you think thus far. Also, the PH has a little play when at full droop. I can rotate it a little bit and am thinking I may need to tighten it up some to remove the little bit of play.
You can see the small polished part on the top of the diff cover. I do not think this is the major contributor.
Here is where it is hitting the tank. I think this is more from squatting under hard acceleration more than anything. I don't think this makes enough contact/restriction to cause the loud pop I can occasionally hear.
This is the upper PH bar bracket. I think this was moved from flying over the curb about a year ago. Since the marks are rusting over, I don't think it is moving at all, but may need to be adjusted to get it back on center.
This is the driver side rear bump stop. Looks to have roughly a 1/4" of clearance with the 315 Nittos.
This is the passenger side bump stop. It is making contact with the midpoint of the sidewall. Since these are 315s on a 9.5" wheel, it flares a little bit towards the tread. The tire didn't appear to have any major scuff marks that you would think this kind of contact would make, much less at speed.
Keep in mind, all of these pictures are at full droop. With it being at full droop, and just eyeballing it, the rear end seems to sway about 1" towards the driver side. Since this is a PH setup, I know it has a small arc as it travels through its range of vertical motion, but I do not know a standard distance or specifications. I will have to drop a bob at compressed high and see where it is. I am also going to raise it up tonight and support via the rear end versus the subframe to check that mount at ride height.
Let me know what you think thus far. Also, the PH has a little play when at full droop. I can rotate it a little bit and am thinking I may need to tighten it up some to remove the little bit of play.
08-05-2010, 07:42 AM
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Yea, thats what I measured the other night. I attempted to fix it last night, BUT the axle needed to go towards the DS by a 1/4" which would of pushed the bump stop even further into the tire. I finally got it adjusted right and went to find a my grinder. Friend borrowed it a while back and never returned it so now I have to go get it from him.
From the make shift plum bob, I got 2 1/2" from wheel center to line on the PS and 3" on the DS. I also checked the wheelbase. It was tweaked by about 3/16-1/4" favoring a shorter length on the PS.
From the make shift plum bob, I got 2 1/2" from wheel center to line on the PS and 3" on the DS. I also checked the wheelbase. It was tweaked by about 3/16-1/4" favoring a shorter length on the PS.
08-30-2010, 08:18 AM
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Found the noise...
I also did a bunch of tweaking before finding this. I did some grinding on both bump stops and ended up centering the LCAs with the subframe, which ended up pushing the rear axle even more off center, but as long as the LCAs are parallel and pushing the car forward, that is all that matters to me.
I lifted it up to put the stock sway bar end links back on. My thought process was that this was around the time the rear end started making noise. Usually when I lift the rear end, I support the uni-body and let the axle hang at full droop, but that is a major PITA to swap end links with position of the sway bar in full droop. This time I supported the axle, and I could hear the clunking and weird noises getting it into position. Then I saw this. The driveline angle is bass ackwards, 3* positive, and the axle needs to move forward about 1/4-1/2". So I will tweak on that this week.
I also did a bunch of tweaking before finding this. I did some grinding on both bump stops and ended up centering the LCAs with the subframe, which ended up pushing the rear axle even more off center, but as long as the LCAs are parallel and pushing the car forward, that is all that matters to me.
I lifted it up to put the stock sway bar end links back on. My thought process was that this was around the time the rear end started making noise. Usually when I lift the rear end, I support the uni-body and let the axle hang at full droop, but that is a major PITA to swap end links with position of the sway bar in full droop. This time I supported the axle, and I could hear the clunking and weird noises getting it into position. Then I saw this. The driveline angle is bass ackwards, 3* positive, and the axle needs to move forward about 1/4-1/2". So I will tweak on that this week.
