Lateral trailing arm movement, Nuts are tight, still wiggles. What next? |
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Lateral trailing arm movement, Nuts are tight, still wiggles. What next? |
Jeff Hail |
Dec 13 2016, 11:16 AM
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#21
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Senior Member Group: Members Posts: 1,141 Joined: 3-May 07 From: LA/ CA Member No.: 7,712 |
So the money shot would be what the pivot shaft and the polybronze bushing look like and how installed. Pics would be helpful. In my experience all PB bushings should be fitted and checked for play without the zerk fittings installed. I have installed a few sets and in various folks arms. What I find is the inner arm bushing sleeves are many times out of spec for what ever reason. They may be just made that way? I don't like the idea of chemical welding urethane to the arms so I find copper shim stock works well. I dab of JB between the arm and shim stock plus the zerk fitting keeps it from rotating. Easy no fail solution. The other problem I have found is with the pivot shaft to bronze fitment. The one in the photo does have lateral play and this is a new unit that was assembled only. I can say for certainty its not a wear issue but simply poor quality control. Luck has it that one of the other bronze sleeves is tight so mix and match works out by swapping the loose one for a tight one. So yes the money shot is when the poles in the hole. Attached image(s) |
ChrisFoley |
Dec 13 2016, 11:24 AM
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#22
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I am Tangerine Racing Group: Members Posts: 7,962 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
... The other problem I have found is with the pivot shaft to bronze fitment. The one in the photo does have lateral play and this is a new unit that was assembled only. I can say for certainty its not a wear issue but simply poor quality control. ... IMO, the shaft to bushing fitment isn't from poor quality control. The tolerances are loose because the installed bushings are never truly co-linear. Close tolerance bushings would bind in that case. |
Jeff Hail |
Dec 13 2016, 02:55 PM
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#23
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Senior Member Group: Members Posts: 1,141 Joined: 3-May 07 From: LA/ CA Member No.: 7,712 |
... The other problem I have found is with the pivot shaft to bronze fitment. The one in the photo does have lateral play and this is a new unit that was assembled only. I can say for certainty its not a wear issue but simply poor quality control. ... IMO, the shaft to bushing fitment isn't from poor quality control. The tolerances are loose because the installed bushings are never truly co-linear. Close tolerance bushings would bind in that case. Hey Chris, Merry Christmas and Happy Holidays to ya! I get that but one bronze bushing is so loose it actually clacks when you rock it by hand on the pivot shaft. The remaining three are snug. With the durometer of the urethane bushing enough deflection is present to allow for any mis-alignment however small so as not to cause any bind. Loose tolerance provided and floating on a thin layer of grease. On the positive side mix and match of the bronze bushings solves the problem. This is not the first time I have seen this, its the bronze that have slight variances. Even on the far end if this equated to a 32nd of an inch in toe change I would not lose sleep over it. |
Matt Romanowski |
Dec 13 2016, 03:05 PM
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#24
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Senior Member Group: Members Posts: 878 Joined: 4-January 04 From: Manchester, NH Member No.: 1,507 |
Any amount of dynamic toe is a problem, IMHO.
It doesn't take much wear of the bushings (less than .005") to create some lateral play and create a bit of a problem. The shimming needs change depending on how tight you had them initially and how they wear. At least in my experience. |
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