T bucket hobbles when driving

[greenmachine]

Every time I drive my t-bucket, it rides almost like it has a hop to it. It’s hard to explain, but similar to a grocery cart with a bad wheel that bounces. I know that one of my rear tires has a flat spot in it from where it sat and went flat all winter due to having a bad wheel. I’ve since replaced the wheels, so the tire doesn’t go flat anymore. Just looking at the tire now on the new wheel, I don’t notice a flat spot, but the tire shop that put it on the new wheel told me that it has a flat spot. I’m not sure if that’s what is causing it to have a bounce or not. My other thought is that it could be where the car doesn’t have front shocks. It only has leaf springs on the front. I notice when I’m riding down the road, the front end kind of sways side to side a little and that may cause the car to feel like it has a hobble. What are your thoughts on it? A mechanic that I know seems to think that it’s because of not having actual front shocks is the cause, and not due to the flat spot on the rear tire, but I just wanted to get some more opinions from some t-bucket owners before spend more money on tires or shocks. Thanks

 

[Spanky]

Does your car have a Panhard bar? Shocks by themselves don't cure wobbles or hobbles. They just dampen the up/down motion of the front axle. Have you tried adjusting the toe-in/toe-out? Some cars like a little bit (1/8") of toe-out. Try it on yours and let us know what happens.

 

[greenmachine]

Thanks Spanky! Here is I picture of my front end

 

[lincolnuT]

Of the three Buckets I have driven (owned) all of them liked Toe Out around 1/8 inch to solve that death wobble......Now I wound up putting Shocks on all three and that sure helped with with the front end problems....

 

[greenmachine]

Of the three Buckets I have driven (owned) all of them liked Toe Out around 1/8 inch to solve that death wobble......Now I wound up putting Shocks on all three and that sure helped with with the front end problems....

Do you need to typically hit a certain speed to experience death wobble? I can be going 25-30 mph and you feel a definite hop like it’s bouncing.

 

[greenmachine]

Do you need to typically hit a certain speed to experience death wobble? I can be going 25-30 mph and you feel a definite hop like it’s bouncing. It feels like the back end is hopping. My local mechanic drove it down the road and he thinks it is starting in the front end of the car due to not having shocks, and that’s causing the bounce. He didn’t know that one of the rear tires had a flat spot though until afterwards.

 

[Spanky]

Have you checked your rear wheels for out-of-roundness or wobble? Have someone follow you and look carefully at your rear wheels when you get up to speed.

 

[greenmachine]

Have you checked your rear wheels for out-of-roundness or wobble? Have someone follow you and look carefully at your rear wheels when you get up to speed.

I haven’t done that, but that’s a great idea

 

[409T]

You can jack the rear end up so that the tires aren't on the ground, prop your hand on a crate or can or something so that you can hold a pencil with the point 1/8" or so away from the tire. Have someone spin the wheel/tire. It doesn't have to rotate fast, just watch and see if the gap between the pencil point and the tire changes during the tire rotation. And of course don't move the pencil.

 

[greenmachine]

I got home from work the evening and raised the rear end off the ground and put the car into gear. I could definitely see the tire with flat spot because it was fairly wobbly and hopping up and down when it turned. I’m not sure if that’s all of my problem, but I’m sure it’s at least part of it.

 

[PotvinGuy]

What tires? Bias-ply will wiggle; we must run radials. I like Hoosiers. I ran without front shocks for years. Adding them:


...fixed lots of monkey motion. I'm bragging a bit; those are Houdailles (originated in France, called Armstrongs in
U.S), adjustable rotary hydraulic shocks, hard to find. All cars had them until 1948, when tube shocks were invented. Fun fact to point out. Also, have all 4 wheels balanced and then do a front alignment. I run 1/8 inch in.

 

[PotvinGuy]

No Panhard?? Front end is just hanging on spring shackles? Need to control side-to-side motion somehow. Lemme think on it.

 

[409T]

https://tbucketeer.com/attachments/171148_re-jpg.25180/

No cross-steering, hence no Panhard bar.

 

[Spanky]

No cross-steering, hence no Panhard bar.

I thought it was the other way around . . . no need for Panhard bar with cross steer. I'm running cross steer without a Panhard and no problems.

 

[409T]

I believe with cross steering it depends on where the steering box is mounted. If the box is mounted on the frame, the drag link is trying to push or pull the axle away from or to the frame. Think of what would happen if you had no leaf spring. In theory the axle would move side to side with the side to side movement of the drag link. In reality it would probably be the frame that would try to move to or away from the wheel because the tire is on the ground holding the axle in place. The leaf spring is there to keep things from moving up and down, not right to left. Hence the possible need for a Panhard bar with the steering box attached to the frame. All depends on how good a job the spring and shackles do fighting the lateral forces.

 

[LongJohn]

I think with the limited vertical movement being so limited and the side load on the shackles the need for a panhard bar is minimal. I have never tried to push an axel side to side to see what happens. Might be a fun thing to try. I have torsion bars on my new car so it’s a moot point.

 

[Spanky]

Ford used cross steer on everything after '35 and until '47 never needed a Panhard. The only reason they changed was the addition of longer shackles to the Ford line for '48.

 

[409T]

The only reason they changed was the addition of longer shackles to the Ford line for '48.

That's what I was trying to say. If the spring and shackles can handle the lateral movement you don't need a Panhard bar, if not you do.

 

[HenrysT]

Ideally the springs are suppose to be under slight tension when you install them with NO weight on them, shackles running horizontal. With weight, the shackles are suppose to be at a 45* angle to horizontal