Hi all,

I bought a 1974 corvette 5 month ago. Driving it was a real pleasure. I live in south of France and it is a perfect weekend car.

But now I am getting an issue with it.
When I accelerate, the back of the car slide to the right. And it is verry dangerous now to drive it. When I press the accelerator I heard a "CLACK" and the and de car drift to the right. When I am releasing the accelerator the same thing append but she is sliding on the left.

I am researching since a month now but without any succes.

Anyone have a idea of what can be the issue.

Cheers

Jeremy

 

You're going to have to get under the car and look for loose or broken suspension parts, paticularly in the rear.

 

Could be either left or right trailing arms shims have fallen out.

 

Try jacking the rear up and performing the simple wheel bearing check....with your hands at 9-3 o'clock positions on the tires outer edge pull/push alternating to see how much play your rear wheel bearings have more than 2-4mm of play would be a concern about the bearing going bad....then grab 12/6 position and repeat....this play is the half shaft/side yoke play.....more than 3-6mm of play would be concerning. I think you are going to find excessive play at the 12/6 position due to someone running the Corvette with its rear in the air and the suspension at full drop.....doing this will often cause the retaining clip on the side yoke to fail and pop out of its groove on the yoke.....the clip is then free to cause wreckage in the differential assembly if it lodges between gears or into bearings. There are many other potential trouble spots in the suspension areas such as the already mentioned wheel alignment shim packs, strut rods, the half shafts ( which not only drive the wheels but are the upper suspension link ), differential crossmember mount bushings, even frame rust issues could be the source of your problems, it will require a process of inspection and elimination of potential sources of your problems. You should by a GM service manual to read and learn about maintenance and rebuilding procedures on your vintage sports car. Wilcox Corvette has service manuals available check their web site for " manuals " for your 74.

 

You're definitely going to have to get under there and have a look. The first test of course is trying to move the rear wheels.

I just bought a 76 that I knew needed some rear end work. I could hear some noise coming from the rear end when we took it for a test drive.( I bough it anyway)

When I got it up on a hoist and checked the right rear it was pretty amazing how shot the U-joint was. There was absolutely no doubt she had had the green weenie.

While you have the car up get under there and start spraying everything with penetrating oil.

Best advice, if you have to remove the 1/2 shafts use an impact gun to break the outer U-joint bolts loose...ask me how I know!

Also about the hardest part (most muscle) was getting the camber adjusting bolts to move the trailing arm far enough outboard so I could get the 1/2 shaft back in position. The camber strut actually moves quite a distance once you snort on it.

If you need any publications are parts mailed to you let know. I'll certainly help if I can.

PM me anytime.

Larry

 

 

Thanks guys for your help. I have been under the car but could not understand from where the issue is coming. Think I will have to call a mechanic to help me.
Will keep you posted.

 

Hi guys,
I finally found what was the problem.I lift up the car with a bridge to have a better understanding. And the problem comes from the Trailing Arm Alignment Shim. These are just gone.
So it was nothing to worry about.
Thanks for your help guys.

 

Glad you found it. Your description of the problem made it very easy to diagnose the cause. It's actually not rare to hear of such things happening, many 'mechanics' leave out the cotter pin meant to hold the shims in the frame pocket.

 

I am also missing the Trailing Arm Bushing, is it easy to change ?
I am thinking of buying this http://www.ecklerscorvette.com/corve...Product_Viewed

What do you think ?

 

Poly bushings are a poor choice for that and most other locations.

This is a better kit

http://www.ecklerscorvette.com/corve...1963-1982.html

 

Thanks, removing the trailing arm for replacing the bushing is it a big work ? Have you already done that ?

 

Yes, it's a major job. There's many threads here describing the process.

 

Many thanks for your help. Will check the threads.

Cheers