1935 Dodge , Vibration at about 40mph.

[Guest Ned Kikly]

I get a good vibration that shakes the whole car when I reach 40mph,then seem so diminish when I reach 50mph. I have had the wheels balanced. It still vibrates when I put it in neutral at that speed. Doesn't seem to be the engine as cause. Could it be alignment or drive shaft out of balance?

[Phil 32DL6]

Have you checked the U-joints?

[Guest Ned Kikly]

Would U- Joints vibrate when not under power? There doesn't seem to be any play in drive shaft. Thanks for your comment..

[hchris]

Have you thrown a weight off the tail shaft ?

Is the tail shaft mounted park brake tight and secure ?

Is there is a possibilty of bent rear axle ?

If all of the above check out, I would be replacing U joints and balancing the tail shaft if you are sure the wheels are running true and balanced.

[Guest JohnArthurSpinks]

Ned,

The '35 Dodge used a Detroit Ball and trunnion type universal on either end of the tail shaft.

After many many hours of use they do wear somewhat so you sahould not be able to detect any sideways movement in any part of the universal.

It is very easy to check by sliding under the car and grabbing hold of the shaft and then shaking it as hard as possible from side to side.

You should not feel any side movement at all.

If so then the universal(s) will need replacing.

By the way I am assuming that the Dodge still has the original type universal in it.

Check to confirm if the universals are covered by either a rubber or leather type flexible cover.

Cheers

John Spinks

Aussie C9 Chrysler Airflow Coupe

[Phil 32DL6]

You might have someone (or yourself) follow behind in another car to see if there's anything visible going on with the tires/wheels/shocks as speed increases.

You can also jack up the back end and run it through the speeds as a test to isolate the cause.

Edited October 1, 2009 by Phil 32DL6 (see edit history)

[nearchoclatetown]

Did the vibration just start? or always there? What recent work was done?

[Guest Ned Kikly]

Thanks for all your possible solutions.. I just purchased the car 3 months ago and it is very orginal..with 42 K miles on it .. and not much has been removed from original. The covers are still on the U-joints.. and look to be leather. The car is pristine and doesnt look like it was abused. I will wiggle the drive shaft by hand and see if there is any play.. Thanks again.

[nearchoclatetown]

How old are the tires? Could one of them have a tube that's all bunched up. Were the tires flat when you bought it? Could you let all the air out of the offender and repump it up? I know you said they balanced, BUT tube tires are known to cause wobbles.

[RickBrinker]

The best way to check the u-joints is to remove the shaft and apply a little pressure in the direction as if it was moving forward and slide the ball and trunnion in and out and see if you feel a flat spot.It sounds like a drive shaft problem.