 Alignment issues, bent trailing arm? |
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| Alapone |
 Jul 22 2015, 02:54 PM
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#1
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Member  Group: Members Posts: 105 Joined: 4-April 13 From: Nj Member No.: 15,734 Region Association: None  |
I am having trouble getting my car aligned properly. The tech was saying the rear left was set to +1.00 camber. This was noticeable when crouching behind the car. The front alignment was substantially toe-in in order to counteract this.
Rewind 18 months: The car was slid into a curb which resulted in a bent wheel and some damage to the inside trailing arm hook up point (don't have the real term for this but I mean the ear where the inside bolt of the trailing arm hooks to the car. This was all supposed to have been fixed and straight. Last week: Having recently finished a 5 lug conversion which retained the same rear trailing arms I went to go have an alignment done when they told me someone non specifically "something in the rear is bent". How do I go about checking to see what is wrong? I assume autocross guys have good experience with this type of thing. Do trailing arms bend? Is the ear/hook up point the place to start? I'm sure I can find a used straight trailing arm for $100 or so here on the world but what am I up against if it is damage to the ear/hook up? Any advice is appreciated |
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| SirAndy |
Jul 22 2015, 03:07 PM
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#2
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Resident German Group: Admin Posts: 41,651 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
Yes, they do bend and are designed to do just that
It's easier to replace a bent trailing arm than to fix a broken or ripped apart chassis. I recall seeing a technical drawing many years ago that had all the trailing arm measurements and i even recall a jig made to check trailing arms for straightness. (IMG:style_emoticons/default/idea.gif) |
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| EdwardBlume |
Jul 22 2015, 03:31 PM
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#3
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914 Wizard Group: Members Posts: 12,338 Joined: 2-January 03 From: SLO Member No.: 81 Region Association: Central California 
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Andy is correct. The trailing arm on Dads car is bent from a lousy flat tow.
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| bdstone914 |
Jul 22 2015, 09:52 PM
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#4
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bdstone914 Group: Members Posts: 4,523 Joined: 8-November 03 From: Riverside CA Member No.: 1,319 |
Probably a bent arm. Early 70-72 have a different flex brake line bracket than the 73-76. I have them and would sell one for $50 plus shipping. Bare arm no spindle bearing or hub.
Can sell one but you may find one closer to save shipping. they weight about 25 pounds. Did you replace the bushings when you did the 5 lug? I suppose that distorted bushing could cause too much negative camber. |
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| mgp4591 |
Jul 22 2015, 10:20 PM
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#5
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914 Guru Group: Members Posts: 5,375 Joined: 1-August 12 From: Salt Lake City Ut Member No.: 14,748 Region Association: Intermountain Region
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Small hijack here- so does the fact that they're meant to do that (bend vs. more damage) mean that it's not a good idea to reinforce them even if you're running lots more power and weight? (IMG:style_emoticons/default/idea.gif)
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| SirAndy |
Jul 23 2015, 01:33 AM
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#6
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Resident German Group: Admin Posts: 41,651 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(mgp4591 @ Jul 22 2015, 09:20 PM)  Small hijack here- so does the fact that they're meant to do that (bend vs. more damage) mean that it's not a good idea to reinforce them even if you're running lots more power and weight? (IMG:style_emoticons/default/idea.gif) Neither power nor weight are really the issue, especially not for a street car. Reinforced trailing arms make sense for a track car running large sticky slicks ... (IMG:style_emoticons/default/idea.gif) |
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| Alapone |
Jul 23 2015, 05:57 AM
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#7
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Member Group: Members Posts: 105 Joined: 4-April 13 From: Nj Member No.: 15,734 Region Association: None |
QUOTE(SirAndy @ Jul 23 2015, 03:33 AM) QUOTE(mgp4591 @ Jul 22 2015, 09:20 PM) Small hijack here- so does the fact that they're meant to do that (bend vs. more damage) mean that it's not a good idea to reinforce them even if you're running lots more power and weight? (IMG:style_emoticons/default/idea.gif) Neither power nor weight are really the issue, especially not for a street car. Reinforced trailing arms make sense for a track car running large sticky slicks ... (IMG:style_emoticons/default/idea.gif) thanks guys. bdstone, yes we did replace bushings at the time of the conversion because they had worn unevenly. The right rear was completely worn out while the right left (where I have the issue) was not as bad. This leads me to believe the problem with this car may have existed before I owned, or before the incident sliding it into the curb. Though the curb shot I gave it and this issue with the camber are too coincidental to not be related I think. How do I go about measuring the trailing arm to see if it is good? Are all trailing arms the same 70-76? To be clear the tech at the alignment shop told me I have significant (1.00) positive camber on the rear left. (Top of the wheel is farther outboard than the bottom) |
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| rgalla9146 |
Jul 23 2015, 06:18 AM
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#8
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Advanced Member Group: Members Posts: 4,559 Joined: 23-November 05 From: Paramus NJ Member No.: 5,176 Region Association: None
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Hey Andrew
We can remove your trailing arm and measure it against others I have. It should be possible even without a jig. This will determine where the issue is. Rory PS yes, new bushings installed |
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| Alapone |
Jul 23 2015, 07:03 AM
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#9
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Member Group: Members Posts: 105 Joined: 4-April 13 From: Nj Member No.: 15,734 Region Association: None |
QUOTE(rgalla9146 @ Jul 23 2015, 08:18 AM) Hey Andrew We can remove your trailing arm and measure it against others I have. It should be possible even without a jig. This will determine where the issue is. Rory PS yes, new bushings installed haha sry I didn't want to bother you on vacation! talk soon |
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| Dave_Darling |
Jul 23 2015, 04:32 PM
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#10
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914 Idiot Group: Members Posts: 14,990 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California
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The Haynes manual has a photo of measuring the trailing arm and a spec for measurement. As with most of their photos (and words!) it came straight out of the factory manual.
--DD |
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| ChrisFoley |
Jul 23 2015, 04:54 PM
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#11
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I am Tangerine Racing Group: Members Posts: 7,927 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None
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There is a 1.5 degree negative camber built into the trailing arms.
That means if you have the pivot shaft perfectly level and the axle at the exact same height as the pivot shaft, the hub will have a negative camber of 1.5 degrees. Any other results means the trailing arm is bent. |
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| rgalla9146 |
Jul 24 2015, 05:30 AM
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#12
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Advanced Member Group: Members Posts: 4,559 Joined: 23-November 05 From: Paramus NJ Member No.: 5,176 Region Association: None
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great information, better than just a comparison
thanks Chris |
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| Alapone |
Jul 24 2015, 07:44 AM
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#13
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Member Group: Members Posts: 105 Joined: 4-April 13 From: Nj Member No.: 15,734 Region Association: None |
QUOTE(rgalla9146 @ Jul 24 2015, 07:30 AM) great information, better than just a comparison thanks Chris thanks guys |
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