Finally after 5 years

[Those]

Im posting this because it may help someone else. The car is a 1973 Cuda 340 4 speed car that I’ve owned for 7 years and been driving for 5 years and about 10,000 .miles. I’ve been chasing a front end vibration all that time. It starts at 65 mph and stays at any speed up from there. It doesn’t get worse just stays the same. In that time I have replaced every piece of front suspension. I never felt like it was a vibration because I couldn’t feel it in the steering wheel . I could see the front fenders moving or bouncing up and down when it would start. To get to the point I lowered the torsion bars 3 full turns and about 1 inch on the height and the problem is gone. In all my research on the internet about suspension issues I didn’t see anything about having your torsion bars to tight could cause problems. Most say set the front as high as you like and go get an alignment. Any opinions are welcome.

 

[Syleng1]

Back Ground- I spent plenty of time as professional mechanic and have been to Hunter Alignment school twice in my career.

The vibration you feel could be caused by a few things. Alignment is not one of them.
I'm not saying the front end is not out of adjustment, but a broken/ shifted belt in the tire, bent rim etc, etc will all cause vibration BUT if in the front end the steering wheel will shake. (try to rotate the tires left ot right and see if it goes away or changes)
The other options are - drive shaft vibration (out of balance on the trans side or bad u joint), engine vibration - harmonic balance slipped a bit for example or ignition breaking down under load.
Rear axle vibration being transmitted they floor
rear tires - also transmitted thru the floor.

I had a car once that did a simular thing. It was the harmonic balance and in high gear (under most load and running in final gear on highway speeds)
It slipped due to a broken down rubber. just a few degrees but gave my engine a high rpm speed vibration. Felt it thru the floor.
A bad wheel bearing front or rear can do that as well- no shake in steering wheel but vibrate thru the car.

These are the worst to diagnose because you need to be at high speed to verify.
Good luck,
Joe

 

[ChuckDock]

Im posting this because it may help someone else. The car is a 1973 Cuda 340 4 speed car that I’ve owned for 7 years and been driving for 5 years and about 10,000 .miles. I’ve been chasing a front end vibration all that time. It starts at 65 mph and stays at any speed up from there. It doesn’t get worse just stays the same. In that time I have replaced every piece of front suspension. I never felt like it was a vibration because I couldn’t feel it in the steering wheel . I could see the front fenders moving or bouncing up and down when it would start. To get to the point I lowered the torsion bars 3 full turns and about 1 inch on the height and the problem is gone. In all my research on the internet about suspension issues I didn’t see anything about having your torsion bars to tight could cause problems. Most say set the front as high as you like and go get an alignment. Any opinions are welcome.

Thanks for sharing that info. I would have never thought a vibration could happen because the torsion bars are to tight but really good to know for sure!