Custom Trailing Arm Failure

Gen III Camaro Rear On a 1949 Buick- HELP

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Here we go again. It seems that since I put the rear on the car, its been nothing but trouble. I used the rear off a Gen III camaro for the Buick.



Here's what was kept Original at the Rear:

• Springs ​
• Trailing Arms ​
• Spring Perches were transplanted from Orig rear to Camaro Rear ​

Here's what was Added: ​

• New Air Shocks and Mounting locations ​
• New Driveshaft (Custom) ​
• New Panhard Bar (Hotchkis $188.95) ​
• Rear disc Brakes that came on the Camaro Rear ​

Since it's inception the rear has wreaked havoc. It was to Torquey and completely twisted the thin metal factory trailing arms. They were beefed up with new square tubing stock and universat tie rod ends seen here:

With the rear- I cut off the original trailing arms from the new rear and discarded- essentially stripping it to the Differential, brakes & axles. I removed the "clamps" along with the spring perches from the original rear and set to attaching them to the new Camaro Rear. Unfortunately the daimeter of the original Axle tubes was much larger than the camaro's thin axle tubes- So I shimmed it with Steel tubing of the same diameter. ​

Drivers side has held Up:

P***enger side has not:
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As you can see- Almost Everything else at the rear has been steel reinforced...twice. ​

The only weak points are these clamps. Is there another way? I'm Hurting here. Any custom Clamp trailing ideas or experience? ​

Thanks- Frank​

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This is a Buick that used to have a torque tube on the original rearend, correct? But you have now welded the brackets for the arms, which used to have some "give" in the old application, solid to the new axle? And you expect them to not "give" anymore?

Tell me if I'm wrong.

In the original setup the torque tube held ALL the strength, and the arms just kept the axle square left to right. Now the strength is gone and you want the small arms to do all the work. Somethings gonna break, obviously

 

Do you us the 3rd link (torque arm)that the car (camaro)came with. You can't just use some of the parts

 

Yes. It is a Buick. Yes it used to have a torque tube. It never had any give to it on the original application. What held the pumpkin back there was the torque tube. Now- This hold's it back there: Plate Steel.


The original trailing arms were only designed to keep the rear axle from moving fore and aft, in a tension mode. This might be the Give youre referring to. The original setup was also welded to the Axle housing at the top which carries the spring perch and the bottom was connected with 3 bolts as per the current design.

 

Just a question here,but-- When you first put it together did you cycle the rear suspention (without shocks and springs) up and down and each side independently? You are bound up and the panhard bar is forcing the mount to break off.

 

Yup, those wimpy radius rods were not engineered to handle the torque of the rear end.

That was the job of the torque tube.

For the 3G Camaro, this was done with a torque arm that bolted to the front of the differential. Could you incorporate this into your design?

The Camaro used a "two link" - composed of just the torque arm, and a panhard.

Rich

 

I don't know what that is....

but it looks scary.

 

Forgive me, I'm slow. How would I cycle the rear suspention without shocks and springs. The panhard Bar is an adapted one (For 1957 Chevy) that fits the 49 Buick Perfectly.

I feel badly- I think I messed up the design. I didn't know that the trailing arms were not really meant to keep it back there. Apparently neither does the shop where I had the work done. I took it there because after I finished it, we had a rear steer problem. They aligned it, put that heavy duty steel plate on top of the pumpkin where the original Gen3 Camaro trailing arm sat and bolted up THROUGH THE BODY under the rear seat.

I lifted the rear seat last night and to my horror, the plate is starting to flex through the body- metal is ripped.

 

That does look scary. I'm no expert, but I think you really need that torque arm

 

yea, i cant wrap my head around what all that plate is on top of the pig...

are those air shocks in the center behind the housing? exhaust wrapped around in there too... i cant make heads or tails of this setup

 

You are relying on the trailing arms to carry the axle torque reaction that used to be carried by the "torque tube". It's called a torque tube because it prevents the torque from rotating the axle housing up towards the floor, not because the torque goes through it from the transmission.

You essentially have a truck arm style suspension but your trailing arms and bushings aren't allowing for the proper articulation and it is worse now that you "beefed up" your trailing arms. The panhard bar is not the problem, the design of your trailing arms is. Truck arms are made of I beams and are designed to twist as the rear suspension articulates. Your arms can't do this so it twists at the brackets and breaks. That's what I see anyway, if I am missing somethin let me know.

Donny

 

Something Like this you mean??

 

It amazes me that there are shops out there that do **** like this....it is very much time for you to find another shop.

 

HOLEEE ****!!!

Dude, you're rear axle is bolted to your body?!?!?!?

Rich

 

You PAID for that ****?!?!?!? That plate needs to be inserted in the "shop" owners ***

 

A shop that would do something like that is bad news. You really need to find someone who knows what they're looking at to fix that dangerous mess before you end up losing the rear end while driving. Really, bolting a moving suspension part to thin sheetmetal?

 

to "cycle" the suspension to check for trouble with the travel, pull the springs, pull the shocks, and the sway bar, then jack the car up and let it down a few times while watching the suspension...

 

Its' either this or truck arms....maybe a new shop???

 

That would work very well. It is worth noting that the front of the torque arm slides front to rear in that rubber bushing in the front. that's the way it is supposed to be and it works great.

 

Yes, I think you and your shop need to totally rethink the design of this suspension. It sounds like an accident that's already happened. You can't just bolt plate steel between the floor and rear axle and expect it to articulate and survive.

Actually, I wouldn't go back to that shop. Sounds like the kind of place that has NO IDEA what they are doing and shouldn't be designing your suspension.

 

oh man... ya. please, do not drive this thing again untill you fix this mess... and for the record, i'd be jumping all up and down on that shops *** right now.

 

Yep, except I leave the shocks in to ensure proper shock travel....

 

Yes. A shop did this. I feel sick. We gave this guy close to $5,000 to get the rear end fixed. He even said he took it to a pro and had it "laser aligned". Had the paperwork and everything. I want to sue him- but I always like to wait 24hours to make any decisions when I feel upset.

I'm just outside of Philadelphia in Gladwyne, PA. Does anyone know of someone familiar with our fellowship that I could entrust the vehicle to?

It's funny. We have been having SERIOUS problems with the transmission BANGING into gear and it's shot out a waterpump and a set of U-Joints like they were candy. Think I found the problem...

 

Holy ****, take lots and lots of pictures, do***ent do***ent do***ent. Keep a journal too.

 

He also sold me on the idea that those air shocks whould provide a better quality ride than the original oil filled levers that were there originally (still on the front) and man o man does the ride quality ****. It bounces and bangs and if you air up the shocks in the back through a trunk valve it looks like a parade car for Cinco De Mayo.

 

Thank you all for your support. It means a lot.

 

What a shame, that's down right dangerous, the other pictures are what you were looking for and could still be done. I would definetly be looking to get my money back

 

I am speechless!
It is the most incompetent bit of work I have ever seen.
I have seen a lot of stupid stuff but this shows absolutely no concept of knowing anything about suspenson, stresses or even any common sense.
It is a miracle you weren't killed.
I would demand my money back or sue.

 

I'll bet that shop doesn't get much repeat business.

 

In this case, I wouldn't wait 24 hours to break my foot clean off in his ***. $5,000, I'd break both of them off in there. I can hear the sound of everyone shaking their head at this "mechanic's" stupidity and lack of concern for your safety.