Wishbone End Picture - fighting death wobble

[JZSlenker]

Hello everyone,
I'm trying to find a picture of the perch nut end of a wishbone that uses the tapered nuts. Back story... I still have a death wobble at 20mph after changing king pins, king pin bushings , perch bushings and shackles, steering bushing, tie rod bushings, wishbone cap, pitman arm and tie rod ball end. Everything is nice and tight but I still have a wobble. Today I noticed the wishbone ends were a little bit walled out. The shoulders on the perches are pretty good still, although I'll likely replace those. I figured I would add some material back to the end of the wishbone area by tig welding and re drill and machine back into shape to tighten it up. Unfortunately I can't seem to find any good pictures of what it should actually look like. I have an idea but would love a picture of one that is in reasonable shape. Thanks in advance.

[TXGOAT2]

You'll need to repair or replace the worn parts. The forward ends of the wishbone and what they attach to have to be tight and properly shaped to establish and keep the correct wheel alignment and steering angles, particularly the caster angle. It's also important that the wheels be balanced and that that they are structurally tight and that they run true. If the caster is not correct, due to loose, bent, or worn parts, the car will want to steer itself all over the road and it will be especially prone to wobble and shimmy. When the wishbone and related parts are straight and tight, the tops of the king pins should tilt toward the back of the car at an angle of 5 degrees when the car is assembled and sitting on a level surface. For this to happen, all the parts, including the front spring, the axle, the wishbone, the motor mounts, frame, and so forth must be within spec and all joints must be tight.

[Scott_Conger]

Jason

EDIT: my goodness, did I ever do a bad job in reading your original complaint - I was solving what you already knew! Previous advice removed.

EDIT and still pertinent: Don't plan on replacing perches unless you're ready to ruin them and end up in a machine shop to remove them. If you have new bushings in them and the threads are good and not stripped. Leave them alone.

[Dan Hatch]

What did the kingpin holes in axle look like?
Was top one tight? No play?
Did bottom one have good threads in it?
If not sounds like a job for “Stevens Front Axle Tool”.

Second set of questions. Was axle straight? Dan

[TRDxB2]

Hello everyone,
I'm trying to find a picture of the perch nut end of a wishbone that uses the tapered nuts. Back story... I still have a death wobble at 20mph after changing king pins, king pin bushings , perch bushings and shackles, steering bushing, tie rod bushings, wishbone cap, pitman arm and tie rod ball end. Everything is nice and tight but I still have a wobble. Today I noticed the wishbone ends were a little bit walled out. The shoulders on the perches are pretty good still, although I'll likely replace those. I figured I would add some material back to the end of the wishbone area by tig welding and re drill and machine back into shape to tighten it up. Unfortunately I can't seem to find any good pictures of what it should actually look like. I have an idea but would love a picture of one that is in reasonable shape. Thanks in advance.

[JZSlenker]

Mick, thanks! That is perfect. Pretty much what I thought but wanted to be sure.

I have new nuts on the way.
Axle is straight.
Holes were tight just bushings shot.

Out of curiosity, what is the Stevens front axle tool?

[Dan Hatch]

Glad you ask!!! Pictures worth a thousand words.
https://www.youtube.com/watch?v=7DNGT7P79vg

Thanks to Bill for making this video. Dan

[Mark Gregush]

These might help if the taper in the wish bone is worn.
https://www.snydersantiqueauto.com/prod ... &cat=41626

[JZSlenker]

Dan, that’s really cool. I can see that that would be a great solution if the steel itself were damaged. Thanks for sharing.

Mark, I saw those, but I think I can handle machining new tapers after welding more material in. I have a mill at the shop in my office.

[Dan Hatch]

Finding a good axle now (100 years after manufacturing) is all but impossible. I have not seen a good axle at a swap meet in many years.
Stevens tool makes the axle better than Henry made them.?

[TRDxB2]

Mick, thanks! That is perfect. Pretty much what I thought but wanted to be sure.

I have new nuts on the way.
Axle is straight.
Holes were tight just bushings shot.

Out of curiosity, what is the Stevens front axle tool?

Names Frank not a Mick

[JZSlenker]

Not Mick Jagger? I’m and idiot.

[JZSlenker]

Not Mick Jagger? I’m and idiot.

[Altair]

You may have a wheel alignment issue, confirm that both front and rear wheels are running true.
Your rear wheels may be going north and your front wheels may be going south. This can happen with a motorcycle, if the rear wheel is cocked off just a little it will be in conflict with the front wheel. Nothing will show at city speeds, however at higher speeds it will manifest itself, the rear wheel is going one way while the front wheel is going the other.
Wheel alignment alone will not fix it the entire carriage must be aligned. I once had a frame that was hit in the left front corner and left the frame a parallelogram. The frame had to be realigned on a frame straitening jig. I only found the problem when trying to install the engine and the mounts would not line up.

[speedytinc]

Those perch nuts would have to be so sloppy to be your obvious problem.
Check toe in, caster, & wheel bearing looseness. You have appearto have done/checked everything else.

[JZSlenker]

Thanks for all the responses.
Toe in and caster are good.
When holding the front axle and shaking, the only movement seen was in one of the wishbone / nut sockets.

[John E. Guitar]

Hi Jason,

My Tudor had a death wobble at around 20kmh. It was very noticeble going over speed humps. The problem ended up being that it had two left spring perches rather than a left and a right.

It's probably a different issue with your car but it's something that's easy to check if you haven't already.

If you do end up replacing the spring perches be aware that some of the new ones aren't that great.

[Mike Silbert]

I see a lot of discussion about looseness where it does not belong and bent, reversed, and incorrect parts and alignment.
All of these are the most common causes of the death wobble and very important.
But there is one more thing that can cause a death death wobble that people forget about.

On a cross shaft drag link steering system if the spring shackles are binding (or a badly designed panhard bar) it can cause the death wobble.
Locking the correct pivot point on the on the front axle will cause the wheel to steer when you hit a bump.
The axle is supposed to go straight up and down as it travels and in certain cases it can be forced to go side to side as it goes up and down just like you turned the steering wheel.

The bottom line is - while you are looking for looseness make sure there are no binding or locked up parts also.
Mike