Bouncing knock in rear
Thread Starter
Instructor
Joined: Nov 2010
Posts: 201
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From: Corpus Christi Texas
Bouncing knock in rear
I went thru all threads that I could find on the rear knocking, and I replaced the tefflon washer, checked u-joints and hub. Everything was fine. When I finally thought found the knock or one of the knocks was a flat spare tire. Took off and knock was gone for a good long time, I was so happy 
. But wait, there is more to this story.... Anyways one day I decided to adjust hight on car abit. I turned the spring nut, actually not much just trying to evenout the car, maybe off by about 1/4 inch. Then knocking comes back. All I did is turn that spring nut and knocking came back, how can this be?????
Well I thought bushings but I put new bushings in there not long ago.
Could it be the spring?,, I did noticed that bushings were different from old wornout ones. These are Energy Susp Poly Bushings, and the stock were rubber and sort of had a curved fit into upper cup, and new ones just had a small lip. Could it be that adjusting screw could be knocking on sides of spring or retainer cup? Only other thing I have not checked is that I heard that outer control arm joint needs greasing, but the knock is only over bumps, even small pot holes etc...
. But wait, there is more to this story.... Anyways one day I decided to adjust hight on car abit. I turned the spring nut, actually not much just trying to evenout the car, maybe off by about 1/4 inch. Then knocking comes back. All I did is turn that spring nut and knocking came back, how can this be?????Well I thought bushings but I put new bushings in there not long ago.
Could it be the spring?,, I did noticed that bushings were different from old wornout ones. These are Energy Susp Poly Bushings, and the stock were rubber and sort of had a curved fit into upper cup, and new ones just had a small lip. Could it be that adjusting screw could be knocking on sides of spring or retainer cup? Only other thing I have not checked is that I heard that outer control arm joint needs greasing, but the knock is only over bumps, even small pot holes etc...
Team Owner
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Nope, Thats a loose shock.
Look the upper and lower bolts. I just experience this issue when I drove on Mattole Rd. Betty Boop's driver side lower shock nut was loose and it was making that noise everytime it bumped.
Look the upper and lower bolts. I just experience this issue when I drove on Mattole Rd. Betty Boop's driver side lower shock nut was loose and it was making that noise everytime it bumped.
Safety Car
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From: Jacksonville FL
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Thread Starter
Instructor
Joined: Nov 2010
Posts: 201
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From: Corpus Christi Texas
I thought that could also be it,it sure sounds like its every time the shock is bouncing, but it didn't seem to be loose, but then again I could double check. There was an oversized washer there that looked out of place. Is there suposed to be a washer before the nut?
Le Mans Master
Joined: May 2004
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From: Hellinois
Finalist 2020 C4 of the Year - Modified
I also checked my shock mounts, the driver's side top bolt was not loose but it cetainly wasn't tight either. I got a couple turns on it and checked for a wear pattern to see if it had been moving. It had, but only 1/32 inch, maybe. Could have been enough though so I will report back when I drive it again.
Team Owner
Joined: Feb 2006
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From: San Antonio Texas
I had a mystery light knock that turned out to be a slightly bent rear wheel. You couldn't see it while behind me either, but tire balancer noticed it while spin balancing on a machine. New wheel and knocking went away.
Team Owner
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I also checked my shock mounts, the driver's side top bolt was not loose but it cetainly wasn't tight either. I got a couple turns on it and checked for a wear pattern to see if it had been moving. It had, but only 1/32 inch, maybe. Could have been enough though so I will report back when I drive it again.
Team Owner
Joined: Aug 2005
Posts: 34,988
Likes: 515
From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
2018 Corvette of Year Finalist
2017 C4 of Year
2016 C7 of Year Finalist
St. Jude Donor '09 thru '20
