Topic: Trailing Arms Bad?
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How can you tell when the trailing arms are bad and need replace/rebuild? Does it come on gradual or at once? 



1980 L82 (5069 made), Dark Green Metalic (844 made)
Gymkhana Suspension, AM/FM/CB, Sporting a ZZ383.........
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Former Member
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Shirley, NY - USA
Joined: 2/15/2003
Posts: 108
Vette(s): 1980 currently being restored/ cutomized
I had one of mine replaced when my wheel bearing went. The rubber at the pivot point was cracked, I'm sure it was flexing in ways it shouldn't. Other than that, I'm not sure. 

Vmikalinis, 1980 L48 T-tops 4-spd Hurst shifter, edelbrock intake and carb, mid america true dual exhaust into flowmaster 40's. VDB Poly adjustable strut rods. |URL|http://www.C3VR.com/member_uploads/2501_2600/2544/side.jpg |/URL|
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COLUMBUS, MS - USA
Joined: 1/11/2004
Posts: 331
Vette(s): 1972 Coupe; 350 4-speed with GM sidepipes;
Classic White/Saddle
FLA VETTE said: How can you tell when the trailing arms are bad and need replace/rebuild? Does it come on gradual or at once? ![]() |
In a trailing arm you are dealing (primarily) with either the forward pivot bushing or the wheel bearing/spindle assembly. As a general rule, these parts deteriorate over time. If their deterioration goes unremedied, that's how sudden failures commonly occur. Usually we get lots of warning.
Wobbly wheels and jumpy cornering can be caused by worn bushings (trailing arm or strut rod), loose bearings, bad shocks, worn out spring liners . . .
Grinding or rubbing noises can be from wheel brakes, parking brakes, wheel bearings, half-shaft "uni-wiggles", loose side yokes, worn or chipped ring gear or pinion, posi-traction "clutch" assembly . . .
What, exactly, is your car doing (or not doing)? More info, please. We'll be glad to help.

John

Kingston, PA - USA
Joined: 11/26/2003
Posts: 636
Vette(s): 1977 L-82 originally white/buckskin interior.
Currently undergoing a frame-off resto. and modifications.YEEHAW!!!
If you can get in there, and just take a close look, that will tell you much. The trailing arms are a horrible design, consisting of two halves, stitch welded together. If you can poke between the stitch welds on either the top or bottom of the arm, they're gone. Also, check real careful at the point where your spring bushings rest on. Mine has metal practically peeling off. This can cause your spring end bushing to literally shoot out the bottom. I was able to remove a lot of metal on mine, after disassembly, just by peeling the metal off with my fingers. Good luck, that job really sucks. If you're doing it yourself, remove the front pivot bolt with a sawzall. Trust me, just save yourself the time and aggravation of trying to get that bolt out. Chances are, it ain't gonna budge on you. 

So what are we talking for rebuilt trailing arms?
I think I need both sides as my wheels wobble as I drive.

I think I need both sides as my wheels wobble as I drive.

|IMG|http://www.C3VR.com/member_uploads/3701_3800/3714/duskbgoddesssmall.jpg|/IMG| |B|Semper Fidelis! |/B|
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COLUMBUS, MS - USA
Joined: 1/11/2004
Posts: 331
Vette(s): 1972 Coupe; 350 4-speed with GM sidepipes;
Classic White/Saddle
DAVII
Wheel wobble is commonly caused by loose wheel bearings. There is a large spindle nut behind the half-shaft wheel flange. The end-play on that nut should be between .005" to .008" (there are a couple of recent threads on this in the suspension forum). Start with that adjustment. If that's the problem, you're in and out in a day (assuming no special order parts break during the teardown). In order to get at the spindle nut you have to remove the rear spring bolts and rear strut rods in order to swing the trailing arm away from the half-shaft flange.
Because you have to detach or completely remove two-thirds of the rear suspension for this adjustment, it is the prime opportunity to closely inspect the condition of all the system components. Plan on replacing the rear spring bolts and spring cushions ($40), camber cams ($25), spring liners ($50) and strut rod bushings ($30) even before you start. And I totally agree with the advice to use a sawzall to get through the forward pivot bolt. Soak the pivot end with penetrating oil for a day first to get the shims out (carefully noting the original positions of the shims)and try to work it loose. Be careful about throwing sparks - 'cause you're right under the fuel tank.
Trailing arms with bushings will run $400 for the pair. Complete ready-to-bolt-on trailing arm assemblies (arm, spindle, bearings, spindle support, rotor) are $900 each. Please read the threads on rear wheel bearings and ask all imaginable questions before buying either one.
Hope this helps. Good luck
John
|UPDATED|5/8/2004 4:20:36 AM (AZT)|/UPDATED|
Wheel wobble is commonly caused by loose wheel bearings. There is a large spindle nut behind the half-shaft wheel flange. The end-play on that nut should be between .005" to .008" (there are a couple of recent threads on this in the suspension forum). Start with that adjustment. If that's the problem, you're in and out in a day (assuming no special order parts break during the teardown). In order to get at the spindle nut you have to remove the rear spring bolts and rear strut rods in order to swing the trailing arm away from the half-shaft flange.


Because you have to detach or completely remove two-thirds of the rear suspension for this adjustment, it is the prime opportunity to closely inspect the condition of all the system components. Plan on replacing the rear spring bolts and spring cushions ($40), camber cams ($25), spring liners ($50) and strut rod bushings ($30) even before you start. And I totally agree with the advice to use a sawzall to get through the forward pivot bolt. Soak the pivot end with penetrating oil for a day first to get the shims out (carefully noting the original positions of the shims)and try to work it loose. Be careful about throwing sparks - 'cause you're right under the fuel tank.

Trailing arms with bushings will run $400 for the pair. Complete ready-to-bolt-on trailing arm assemblies (arm, spindle, bearings, spindle support, rotor) are $900 each. Please read the threads on rear wheel bearings and ask all imaginable questions before buying either one.

Hope this helps. Good luck

John
|UPDATED|5/8/2004 4:20:36 AM (AZT)|/UPDATED|
Thanks for the replies. I was just curious since the trailing arms is is one area that has not been touched yet. I've seen allot of info on the difficult job for replacing these but not much info on how to know when they are bad or in need of replacing.
I've replaced most of the rubber bushings on the car with poly during the last year. Recently I've developed a new squeek somewhere in the rear and I now have a composite rear spring so I know it can't be that. Well, I guess I will do a visual inspection next time I have the rear jacked up and in the meantime I'll keep an eye on the squeek to see if it gets worse.
I've replaced most of the rubber bushings on the car with poly during the last year. Recently I've developed a new squeek somewhere in the rear and I now have a composite rear spring so I know it can't be that. Well, I guess I will do a visual inspection next time I have the rear jacked up and in the meantime I'll keep an eye on the squeek to see if it gets worse.



1980 L82 (5069 made), Dark Green Metalic (844 made)
Gymkhana Suspension, AM/FM/CB, Sporting a ZZ383.........

Hot Springs, AR - USA
Joined: 4/24/2004
Posts: 3236
Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
Davii said: So what are we talking for rebuilt trailing arms? I think I need both sides as my wheels wobble as I drive. ![]() |
rebuilt arms with everything on them are 399 each with 300 core..
they come with a new rotor and stainless parking brake setup in them ready to bolt on...
new ones are about 799 per side..
a rear wheel bearing assembly by itself is 315..

Lawrenceville, GA - USA
Joined: 10/25/2002
Posts: 100
Vette(s): 1968 427 coupe and 96 LT4 six speed Gran Sport clone
That squek or squealing noise could be your inner and outer spindle bearings running on the last of the grease originally used when the car was assembled at the St. Louis plant way back when. I drone my 68 for about two seasons with that squeal until the outer bearing on the left side let go and 3 of the timkin rollers came out of the bearing cage.Tore the crap out of my spindle as I discovered on diassembly. Not trying to scare you but be careful, if you lose the inner bearing the spindle could shear off and exit through your wheelwell. Very ugly-very pricey. Well, good luck and post-back if I can help-Phil

Lawrenceville, GA - USA
Joined: 10/25/2002
Posts: 100
Vette(s): 1968 427 coupe and 96 LT4 six speed Gran Sport clone
I rebuild trailing arms for my part-time fledgling shop, and I bought all of the setup, disassembly, and clearance tools to do the arms in my 68. I normally charge 300 a side for oem parkbrake shoes or 350 for stailess shoes and hardware. That is assuming everything is reusable, i.e. arm, spindle, bearing housing, and the like. This includes Timkin races, bearings, seals, the appropriate hi-temp bearing grease, and a new front bushing. Also chemical dip to remove any rust from the arm and related bolt on components. Regards-Phil 

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