Play causing front end shake? *UPDATED 8-23-12*

[Franchise_24]

On my '28 if I hit a bump just right my whole front end starts to shake real bad. So much so that I pretty much need to come to a complete stop and start going again. My wife saw it happen the other day and the front tire she saw she said looked wobbly like it was going to fall off. I jacked the front end up and checked it all out. Kingpins appear good, everything is tight, but there is a tiny bit of play in the steering box. Could this play be causing what I am describing?

[mass A man]

No, I don't think the problem is in the steering box. I have play in my old truck's steering box and I never get "the wobbles" in my front end and I hit plenty of bumps up here in New England. Maybe a broken or worn out spring assembly in the drag link ends or tie rod ends, if you are sure the king pins ARE OK. I guess you found the front wheel bearings in proper adjustment when you were checking the king pins. Proper front end alignment needs to be verified along with a good original angle of support at the wish bone ball under bell housing.

[BRENT in 10-uh-C]

I would agree with Mass A Man that everything is not tight, ...and I too would begin at the front radius rod ball. As to answering your question about it being the steering box, a sharp turn in either direction should temporarily remove any slack in the steering gear box and should eliminate the wobble for the moment.

[Mike]

I had the same problem, it was loose spring perch nuts.

mike

[mmindling]

Had the same problem with by '28. Uncontrollable shaking when hitting a bump just right. Put new Firestone tires on and never had the problem again. The old tires were aging and the rubber was hard. Had been stumped because I couldn't find any loose mechanical parts.
Another possibility is the Pitman arm, where it bolts to the steering box shaft. This can come loose and cause wobble.

Regards,

[email protected]

[Not George]

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I had this problem on an O/T car, balanced the tires and it was fine

[ora masters]

Originally Posted by BRENT in 10-uh-C

I would agree with Mass A Man that everything is not tight, ...and I too would begin at the front radius rod ball. As to answering your question about it being the steering box, a sharp turn in either direction should temporarily remove any slack in the steering gear box and should eliminate the wobble for the moment.

thanks brent on the steering gear box now i know why my 32 pick up shimmeys

[oldmanandakid]

I found a cracked bearing race on second inspection as I missed it when first checking the bearings.

[tdlmomowers]

I am trying to help Franchise 24 diagnose his wooble. It does appear that the nuts may not be tight on the spring perches at the ends of the spring. They have castlelated nuts on the spring perches, but there are no cotter pins installed. We will tighten these up and install cotter pins and then see what it does. This car was the victim of a lot of jury rigging before Franchise 24 got it. We have corrected a bunch of problems and it would appear we still have work to do.

[Loyd Nix]

My 30 tudor would start to shimmy if I hit a bump at low speed. I tightened the drag link set screws and that was that. Easy and cheap--my favorite kind of fix.

[BRENT in 10-uh-C]

Originally Posted by tdlmomowers

I am trying to help Franchise 24 diagnose his wooble. It does appear that the nuts may not be tight on the spring perches at the ends of the spring. They have castlelated nuts on the spring perches, but there are no cotter pins installed. We will tighten these up and install cotter pins and then see what it does. This car was the victim of a lot of jury rigging before Franchise 24 got it. We have corrected a bunch of problems and it would appear we still have work to do.

Just a thought or two to ponder, the spring hanger (shackle) nut(s) really are not supposed to be 'that' tight. IMO, by tightening them you can mask another problem but that really isn't correcting the root problem. Think of it this way, ...if the spring does not have the proper arc, then the eye-to-eye measurement is not correct. This allows the spring hangers (shackles) to rock back & forth on the perches. While this generaly will not cause a shimmy, it can create an issue when a severe bump is encountered as it allows the frame/body to sway affecting the drag link position in relation to the steering arm. The results are usually the vehicle will dart when a bump is encountered.

I must be real honest in that we could write a book listing all the possibilities that you two should be looking for. Steering arm balls that are worn, or incorrectly pre-loaded can cause a shimmy. The same mindset applies to the drag link. Truthfully, I cannot help but think someone who grabbed one of the front wheels at the 9 & 3 o'clock position and violently shake it back & forth should allow someone else to see where the slack is.

[1931 flamingo]

IF strg box is good and mounted to frame tight, start with the pitman arm and work forward. Also ck the wishbone mounting and the ball for not being egg shaped. Wheel brgs correctly adjusted.
Paul in CT

[Franchise_24]

Thanks to all for the great replies. Hopefully we can get it looked at this week and report back with some findings.

[Brobrian]

One of my A's wobbles and the other doesn't. This is a famous A problem. I've bee tracking this down for years. Thought I had it licked a bunch of times.


Here are some of the things I've done with little lasting effect:
Check wheel bearings and axle nuts.
Replace wishbone ball cup & springs, add robber ball sleeve.
Decrease air pressure in front tires for less jarring
Rebuild worn gear and sector bearings
Tighten pitman arm
Check for play at the king pins.
Increased toe in (actually made the biggest change).

Probably any one of these could have produced the wobble or something similar and should be checked on a car that wobbles. But, after replacing the worn steering parts on the 31 pu I've decided that there is likely wear on the coupe's tie rod ends. That's what I'll replace next.

In the mean time my grandson gets a kick out of it when I turn hard back and forth to get the wobble to stop.

[Louis]

Originally Posted by Franchise_24

On my '28 if I hit a bump just right my whole front end starts to shake real bad. So much so that I pretty much need to come to a complete stop and start going again. My wife saw it happen the other day and the front tire she saw she said looked wobbly like it was going to fall off. I jacked the front end up and checked it all out. Kingpins appear good, everything is tight, but there is a tiny bit of play in the steering box. Could this play be causing what I am describing?

I had the same problem on my 31 coupe, I gave up and put on some 16" 35 ford wheels and a set of 6.50 X 16" tires, problem gone, I really think some of the org. wheels are so far gone [no matter how pretty they are] that they are a big part of the problem, JMO.

[FL&WVMIKE]

I had that "jitterbug" problem on my 34. I tightened my tie-rod ends, one half turn, and it hasn't happened since. This was about ten years ago.
I was lucky. It can be soooo many things.
MIKE

[Tom Wesenberg]

Originally Posted by FL&WVMIKE

I had that "jitterbug" problem on my 34. I tightened my tie-rod ends, one half turn, and it hasn't happened since. This was about ten years ago.
I was lucky. It can be soooo many things.
MIKE

Tightening the plugs will change the toe-in, so I wonder if the change in toe-in was the fix, or was it the tighter springs on the steering balls?

[Marco Tahtaras]

One of the things that have helped so many Model A's survive all these decades is the fact that they are so forgiving. Nearly every system on the car can function seemingly "normal" with multiple deficiencies. For example your ignition system can have numerous weaknesses such as a weak coil, slop in the distributor shaft, and play in the upper plate, but it will run acceptably. The points may close up very slightly and the car then develop a "miss". However, fixing any one of the other three things may "fix" the problem enough for it to seem "normal" again.

A couple weeks ago Jim Boehmke found an article where what you describe was coined the "death wobble". This is much more severe and not the same as a shimmy although they do share similarities. It's been my opinion (as it was the author's of that article) that death wobble cannot occur without slop in one or more places within the steering and suspension linkages. It's VERY important to note that includes the ball and cups at the back of the front radius rod (wishbone).

With all that in mind, descriptions such as "new tires" or "adjusting toe-in" as a solution obviously worked for folks. However that type of change would simply be enough in those particular cases to make the symptoms lay dormant. As with Brent, I also believe proper investigation WILL locate one or more areas of slop. 10-12 years ago I posted about the pendulum effect at the shackles (spring hangers) with an excessively flat front spring as Brent mentioned but I believe that would also require other contributing factors.

The single most effective way to locate slop requires two people. The car must be on the ground. While one person lays under the front the other person grasps the steering wheel and forcefully rotates the steering wheel back and forth through it's free movement. Spend some time staring at EVERYTHING under there. You will likely see things like the Pittman arm and steering sector shaft moving up and down in the sector housing. If you don't that means either the steering had been at least partially rebuilt or you are NOT looking close enough!

It sounds like you've already checked front wheel bearings and king pins. These are the only checks I can think of that are done with the front end off the ground.

[Franchise_24]

Marco,

Great reply, and thank you for the advice. I hope to get it looked at sometime this week. Working and trying to get 2 peoples schedules to match up is sometimes hard, but as soon as I know something I will post back findings. Thanks again for the great reply.

[tdlmomowers]

We took a quick look at Franchise24's Model A, last evening. There seems to be some play in the rear drag link joint. When you would crowd the steering, you could see some movement at the rear joint. We are going to dissassemble the draglink and check out the parts in the joint. Acts like the spring is either weak or broken. The plug at the rear joint seems to be threaded in too far.

[tdlmomowers]

Has anyone ever installed a steering stabilizer shock on their Model A, and how did it work out? We saw a kit in either Brattons or Snyders catalog and were curious as to if anyone has used one of these.

[1931 flamingo]

I think it's just a "mask" to hide what's wrong. JMO
Paul in CT

[oldmanandakid]

Do Not short-cut with a stabilizer. The kid and I just rebuilt the front end and the further we got into the job the more apparent it became that the car had in fact been a danger. A stabliizer would have masked problems and could have put others in danger. Many 80 year old parts were just plain worn out and others had been improperly installed or maintained. About the only thing that went back in untouched were the king pins and the tie rod itself but with new ends and guts.

It seemed like an impossible task at the beginning but lots of time with the catalogs and Les Andrews book allowed even a couple of rank amateurs (don't be fooled by the promotion from Junior Member to Member) to do credible job. The front end is now tight and I believe major safety issues have been addressed.

I have to give credit to Steve at Bert's who would not sell me a stabilizer, instead telling me to find and fix the problems. Thanks Steve, it the best Model A advice I've had so far.

[Franchise_24]

Well, we are going to work on it tomorrow (Sunday) hopefully, so I hope to have some news to report.

[Franchise_24]

OK, so my father in law helped me go over everything. Only thing that seemed weird was the drag link to the pitman arm had play. Took that apart, seemed okay, put it back together. Tightened it and play was gone. The end was screwed in very tight and not flush with the drag link head, is that an issue? Drove the car tonight and the bad shake is still there. We are running out of ideas, everything else looks good. Thinking of getting the drag link rebuild. Maybe tdl can chime in with any info he thinks is pertinent.

[oldmanandakid]

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If the drag link is boggered I'll bet the tie-rod ends are too. Disassemble and remove the components then inspect carefully, including the balls on the spindle arms and the pitman. If those balls are out of round they must be replaced if a tie rod-drag link rebuild is to do any good.

Did you drop the radius rods and inspect it's parts? We had a mostly decomposed rubber ball which I replaced with radius cap washer.

[rwp]

Originally Posted by mmindling

Had the same problem with by '28. Uncontrollable shaking when hitting a bump just right. Put new Firestone tires on and never had the problem again. The old tires were aging and the rubber was hard. Had been stumped because I couldn't find any loose mechanical parts.
Another possibility is the Pitman arm, where it bolts to the steering box shaft. This can come loose and cause wobble.

Regards,

[email protected]

Same here, after installing new Firestone tires several years ago have not had the shaking anymore.

[Franchise_24]

Originally Posted by oldmanandakid

If the drag link is boggered I'll bet the tie-rod ends are too. Disassemble and remove the components then inspect carefully, including the balls on the spindle arms and the pitman. If those balls are out of round they must be replaced if a tie rod-drag link rebuild is to do any good.

Did you drop the radius rods and inspect it's parts? We had a mostly decomposed rubber ball which I replaced with radius cap washer.

We did not drop the radius ball. Is that a tough task to do?

[Jim Mason]

do you have shocks? if not, a weak front spring can allow the front end to pendulum side to side..

[Franchise_24]

Originally Posted by Jim Mason

do you have shocks? if not, a weak front spring can allow the front end to pendulum side to side..

No I do not have shocks. I have them, but they are not installed.

[Jim Mason]

with out shocks and with a weak front spring the front axle is free to swing on the shackles. I've not tried, but you may be able get the front end off the ground, supported by the frame and see if the axle will pendulum (driver side to passenger side and back)..may be the cause. Don't let it fall on you..

[Franchise_24]

I'm going to redo the tie rod and the drag link with new ends and look at the radius ball and go from there like others have suggested. The thing we saw with the radius ball is to remove the castle nuts to get to it the bolt or stud was just spinning. What is that a sign of?

[Franchise_24]

Originally Posted by Jim Mason

with out shocks and with a weak front spring the front axle is free to swing on the shackles. I've not tried, but you may be able get the front end off the ground, supported by the frame and see if the axle will pendulum (driver side to passenger side and back)..may be the cause. Don't let it fall on you..

Would shocks make that much of a difference? I thought it was just to help with the smoothness of the ride? Is it because they bolt to the frame and then down to the wheel...does it kind of stabilize it or something?

[Marco Tahtaras]

Originally Posted by Jim Mason

with out shocks and with a weak front spring the front axle is free to swing on the shackles. I've not tried, but you may be able get the front end off the ground, supported by the frame and see if the axle will pendulum (driver side to passenger side and back)..may be the cause. Don't let it fall on you..

Unfortunately, suspending it from the frame will temporarily put the arch back in the spring so it can't pendulum!

[Franchise_24]

Originally Posted by Marco Tahtaras

Unfortunately, suspending it from the frame will temporarily put the arch back in the spring so it can't pendulum!

So jack the whole car up and put it on stands then?

[Tom Wesenberg]

Originally Posted by Franchise_24

So jack the whole car up and put it on stands then?

Actually that would be the same as rocking the car as is, on the driveway.

If the bolts spin while trying to remove the castle nuts, then the pockets for the bolt heads have worn down enough for the bolt heads to drop low enough to not catch the cross pin, which is to lock the bolts from turning. This is an easy fix by just making small diameter washers to fit under the bolt heads to act as spacers, which lift the bolts the correct amount to engage the cross pin.

You'll have to lift up on the castle nuts while unscrewing the nuts. Hopefully by lifting up you can engage the cross pin.

[Fred K-OR]

Is the cross pin still in there?

[tdlmomowers]

Yes, the cross pin does appear to be there. How can we gain access to the bolt heads to install washers under the heads? I could not see any way to access the heads of the bolts, they appear to be located in the bell housing and I don't know how to get at them, short of pulling the engine. Is there some hidden access panel or secret way to get at the radius ball bolts?

[Tom Wesenberg]

I switched out my rubber cap with the correct kit about 20 years ago on my 29 Tudor and did the complete job by blocking the wishbone down a few inches and installing the bolts and felt through the hole in the bottom of the housing. It wasn't too bad a job. I made some thin small diameter washers to fit under the bolt heads to take care of the worn recess and used my fingers and some wire to fish them through the hole.

[Patrick L.]

I agree that there is something loose that you're not catching yet.. Regarding the shocks, the lack of them shouldn't cause the shimmy,, but,, they will certainly affect the handling and ride.. You didn't say which shocks you had,, if they are good originals or those from Bill Stipe,, thats good.. If they are the new 'oil-less' ones[I won't mention the makers name],, they are useless..

[Loyd Nix]

Now you'r talking! 80 something years of wear have had to have taken a toll on those moving parts. Do you have Les Andrews books? I found them quite helpful.
Taking the front end apart will be like going to school and will impress you with Henry's cleverness at the time.

[Franchise_24]

Ok, so here is my latest update. Redid the draglink to make sure there is no play there. Did a radius ball rebuild to make sure there is no play there. Also I put my shocks on the front of the car like others have suggested, even tried different tires on the front like others have suggested as well. Every time I hit a bump on the passengers side front tire the car still shakes like crazy. My Dad was helping me yesterday do this so he stood and watched the car when I hit the bump, and we've narrowed it down to maybe the hub is just lose on the front passenger side of the car. I'm going to try to see if it just needs tightened up at the castle nut tonight, or I might be able to try a different hub to see if it makes a difference. If anyone else has any thoughts chime in, but I will report back after I tighten it up and drive around the block. I want to personally thank the man hole cover that I run over to make this happen, he is faithful every time I drive over him for my tests :-)

[Tom Wesenberg]

Has the toe in been set correctly?

Any sign of a bent front axle?

[Franchise_24]

Nothing looks bent Tom, but I am unsure about the toe in or what I am looking for. Would that have to do with the tie rod?

[Patrick L.]

Well,, it sounds like you're pecking away at it.. If you haven't looked closely at the tie-rods,, then now is the time,, before you reset the toe.. I don't remember how the king-pins were or the wheel bearings.. When you go to 'tighten the castle nut' just be careful to adjust the wheel bearings correctly and to not get them too tight..

[Franchise_24]

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Originally Posted by Patrick L.

Well,, it sounds like you're pecking away at it.. If you haven't looked closely at the tie-rods,, then now is the time,, before you reset the toe.. I don't remember how the king-pins were or the wheel bearings.. When you go to 'tighten the castle nut' just be careful to adjust the wheel bearings correctly and to not get them too tight..

Honestly, we couldn't get the tie rod apart. There is no play on the tie rod, so I'm thinking it is probably okay, but you never know...

[oldmanandakid]

Look carefully at that hub and be sure it is sized correctly for your race and bearing set. I had an oversized hub into which someone had crammed the standard size race and bearing. It was the death wobble side.

[Franchise_24]

Ok, will do. Also, I've talked to people in my car club and they are suggesting to check my toe-in, because if my toe is off I'm told that can cause this type of wobble that I'm having. I'm getting frustrated, but I'm slowly chipping away at it. Thanks to everyone who has given advice and suggestions. That's what makes this place so great.

[Larry Seemann]

You say you did a radius ball rebuild. Did that include welding up the radius ball to the original 1.5" diameter? The caster is set at the factory by the position of the radius ball. Think of a bicycle front fork and think how it would be if the front fork didn't extend the front wheel out front of the spindle - the wheel would shimmy so bad you wouldn't be able to steer at all. That's what happens when the radius ball wears down over 80" years - the ball and radius rods go up and the caster diminishes and the front shimmies. Try this: get a fender washer- a 1.5" flat washer with a small hole- and using a large ball peen hammer shape the washer into a cup. Now drop the radius ball and slip the washer up on top of the ball then push the ball back up and reinstall the cap and everything as usual. The washer/cup will hold the ball down and reestablish the caster. It's not a very hard, expensive, time consuming thing to try. I've cured several shimmies this way.
The other thing I've run into is loose spring perch nuts. Are yours tight?
Good Luck!

[Franchise_24]

Thanks for the info, and yes the spring perches are tight.

[columbiA]

You dont have to take the tie rod apart to adjust the alignment.Remove the 2 clamp bolts on tie rod ends,drive a chisel in the slot,if need be,& turn the rod with a pipe wrench as it as RH thread on one end & LH thread on the other.Try to aim for around 1/16"toe-in.If the T R ends are loose, adjust them before setting the toe-in.

[Dave in MN]

Reading everything you checked, I'd start looking at the wheel bearing. Correct races and rollers? JAck up the right front...grab the wheel and check for slop in the bearing fit. You will also discover your king pin fit by doing so.
Hope you find the cause soon!

[Franchise_24]

Dave, from all the checking I've had 3 people say the king pins appear to be good, but how would you know if the wrong bearing is in there? Also last night when I had the wheel off I checked the spindle and there is no play or movement in the spindle, so that appears to be good as well. From what I'm hearing it appears the toe-in could be the cause of all of this, but it seems to simple it seems lol

[Mitch//pa]

Toe in was my shimmy..
After giving the front end a shake down for wear and strg box adjustment the toe fixed it. It took all of about an hour.

[Dave in MN]

Originally Posted by Franchise_24

Dave, from all the checking I've had 3 people say the king pins appear to be good, but how would you know if the wrong bearing is in there? Also last night when I had the wheel off I checked the spindle and there is no play or movement in the spindle, so that appears to be good as well. From what I'm hearing it appears the toe-in could be the cause of all of this, but it seems to simple it seems lol

A loose fit in the bearings was what I was looking for. Sounds like you have checked it with the wheel off. By shaking the assembly with the wheel on, you increase the leverage against the bearings.

Keep looking and let us know when you discover the cause.

Good Day!

[1931 flamingo]

Are the front brake backing plates tight to the spindles??
Paul in CT

[Franchise_24]

Originally Posted by 1931 flamingo

Are the front brake backing plates tight to the spindles??
Paul in CT

Yes they are.

[Rich B.]

I have been thru this in the past with my own Model A years ago, and with friends cars. Some stock, some Hot Rod. All the suggestions are
good, and I followed them all. Some were cured, and some not. The ones that nothing seemed to cure were solved by toe out. If all parts are good, and factory specs with front end alignment it sure wouldn't hurt to try it.
I went from 1/8" toe in to 1/8" toe out, and it cured the problem. Never
had tire wear problem, with many miles on it.

Rich

[MikeK]

Originally Posted by Rich B.

I have been thru this in the past with my own Model A years ago, and with friends cars. Some stock, some Hot Rod. All the suggestions are good, and I followed them all. Some were cured, and some not. The ones that nothing seemed to cure were solved by toe out. If all parts are good, and factory specs with front end alignment it sure wouldn't hurt to try it. I went from 1/8" toe in to 1/8" toe out, and it cured the problem. Never had tire wear problem, with many miles on it.
Rich

I'm not so sure I'd ever want to try toe-out. The Ackermann steering geometry on a Model A was engineered for toe-in on a straight line. Setting it out could produce a rather dangerous situation if you need to make a high speed maneuver to avoid something. The wheel on the outside of the turn will respond even less than the Ackermann compensated design amount. The car will want to go straighter than your learned, instantaneous emergency input into the steering wheel thinks it will. You will misjudge the emergency turn. At low speed, positive toe will make quite a wanderer out of a front end with bias tires.

[Rich B.]

Mike: I understand your hesitancy, and I do not profess to be an
expert. I think I qualified my post by saying one should have all the
correct installed parts. Just speaking from my own experiance I drove that Model A almost 30,000 miles under all conditions with no troubles. I have
several friends with simular results.

I responded since our poster seems at the end of his rope. One thing that has always baffled me is the number of old worn out Model A's
that never seemed to have a problem! LOL

Take care, Rich

[Tom Wesenberg]

"I responded since our poster seems at the end of his rope. One thing that has always baffled me is the number of old worn out Model A's
that never seemed to have a problem! LOL

Take care, Rich"

Yes, that's my car at the moment. I have a very worn out front end to use as a temporary while I restore my original front end. If I jack up the front axle I can move the tires a couple inches by grabbing the top and bottom. I've never had a hint of shake. I haven't even checked the toe-in, but it must be right on by the tire wear and how well it handles.

[Franchise_24]

Originally Posted by Tom Wesenberg

"I responded since our poster seems at the end of his rope. One thing that has always baffled me is the number of old worn out Model A's
that never seemed to have a problem! LOL

Take care, Rich"

Yes, that's my car at the moment. I have a very worn out front end to use as a temporary while I restore my original front end. If I jack up the front axle I can move the tires a couple inches by grabbing the top and bottom. I've never had a hint of shake. I haven't even checked the toe-in, but it must be right on by the tire wear and how well it handles.

Some guys have all the luck!!

[Franchise_24]

Ok, we are gong to attempt to set the toe-in today to see if that corrects the shimmy problem. I'm looking through my Restorer book (which is very old) and it says the car should have a toe-in of 3/16in to 1/4in. Just wanted to see if anyone wanted to verify that those are still the same measurements people still use today? I will report back tonight if we are able to get anything. I see the tie rod has left and right handed threads so you can adjust it without taking the tie rod off, I'm just worried about getting it loosened up to get it to turn. We will see.

[Bob C]

Those figures are not correct, see the link to Marco's site.
http://www.abarnyard.com/workshop/align.htm

Bob

[Patrick L.]

When roads started improving it was found that 3/16-1/4" was too much.. It should be reduced to 1/16 - 1/32" .. It needs to also be set with the vehicles weight on the tires,, measure the back side, roll the vehicle forward and measure the front ..

[Franchise_24]

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OK, the toe-in is set. Found some play in the passenger side of the tie rod. Put new guts in, plays gone. I still have horrible shake when I run over the man hole cover with the passenger side front tire. I'm out of ideas guys and gals. Anyone got any more suggestions?

[columbiA]

Back in the 50,s my "A" would shimmy when I hit a pot hole.It turned out that the LH spindle arm was slightly loose in the spindle.Tightening the nut solved the problem.

[Patrick L.]

Boy, there has to be something loose that just isn't being seen.. Start checking the 'other' stuff like spring perch arms and steering arms,, sometimes you get a little more out of them.. Even check the spring shackles as well as re-checking the radius arms/ball..

[c125bob]

I'm not a seasoned Model A man. Learning stuff every day. Just had mine about a month. It had a ton of play in the wheel and the death wobbles. I spent a good while shaking stuff, jacking it up, greasing and looking for it. On this car it was a sneaky loose pittman arm. The captured bolt behind the arm was bent from overtightening and while everything "looked" good the arm had play in it on the "right bump". There was one down the street that would do it every time.

After I fixed this issue the wobbles were cured and the play in the wheel was gone. Good luck in your search for a cure.

[1931 flamingo]

Spray paint the offending man hole cover with BRIGHT paint and avoid it......................

Paul in CT

[HoarseWhisperer]

After going through the front end tie rods, drag link and even replacing king pins, the cure for the persistent wobble on my truck was replacing the rubber radius ball bushing with original style caps.

There is also the curved radius ball washer #04691 available from vendors if needed.

[Franchise_24]

Originally Posted by 1931 flamingo

Spray paint the offending man hole cover with BRIGHT paint and avoid it......................

Paul in CT

I wish life were that simple Paul lol. I'm thinking of borrowing 2 tires off my coupe for a test on the front of the Leatherback to see if it makes any difference. I switched tires from back to front on the leatherback, but those tires are old and a bit dry rotted, so going to try good tires and see.

[gweilbaker]

My buddy's 34 coupe had a bad case of the death wobble that was cause by under inflated tires. I would have never believed it if I wasn't there to see it, weird.

[Brentwood Bob]

Check to see if spindle arm is bent. Bob

[Franchise_24]

Originally Posted by Brentwood Bob

Check to see if spindle arm is bent. Bob

Spindle arms are fine. I will point out that the toe in was set to 1/4" and I know they say it doesn't need to be that much anymore, but I wanted to verify that that wouldn't be causing the shimmy would it since it was what it used to be?

[quickchange]

Not read all the threads but assume all the obvious has been done & checked & put rigtht but problem is still there,?? My cure having done all above & still there on a fresh resto with 1500 miles on it & was not there to start with , Pulled the steering box, found a bent steering coloum shaft, Only replaced the shaft & its never wobbled again, Bet someone tried to press a new worm on at some stage & bent the shaft,

[Patrick L.]

Without reading all the posts over again,, it sure seems like something is being over-looked,, or,, maybe I should say under-looked.. I think I remember that you are not using shocks.. If you think everything is tight and as it should be then maybe good shocks should be installed and the toe set to 1/16-1/32" .. I'd also suggest a fresh set of eyes looking at this monster,, you never know what someone may see..

[RichPA]

If all else fails have the caster checked on an alignment machine, caster too positive(over 5 degrees) can cause this. If it is, something, possibly the axle is bent. Positve caster is the most common cause of the Death Wobble in modern trucks.

[Terry, NJ]

After reading this, I decided to check the Pitman Arm, ball on my coupe. I miked it and got .860 across the short/worn side. From 1.000 to .860 is .140 (.125=1/8) No wonder it's hard to steer near the locks!
Terry

[Franchise_24]

Originally Posted by Patrick L.

Without reading all the posts over again,, it sure seems like something is being over-looked,, or,, maybe I should say under-looked.. I think I remember that you are not using shocks.. If you think everything is tight and as it should be then maybe good shocks should be installed and the toe set to 1/16-1/32" .. I'd also suggest a fresh set of eyes looking at this monster,, you never know what someone may see..

Yes, it is a lot to read :-) We did install shocks on the front and it made no difference. I put the rims/tires from my good car (the coupe) on the leatherback to verify it wasn't the tires and it made no difference. The toe-in is set to 1/4" which I know they say is not needed to be in that much anymore, but I wouldn't think that would cause an issue would it?

[1931 flamingo]

1/4" too much. JMO
Set it to spec.
Paul in CT

[Franchise_24]

Originally Posted by 1931 flamingo

1/4" too much. JMO
Set it to spec.
Paul in CT

My question is 1/4" was the original spec. Would that *cause* it to shimmy?

[Tom Wesenberg]

Originally Posted by Franchise_24

My question is 1/4" was the original spec. Would that *cause* it to shimmy?

Where or how are you measuring it? I think Marco has some information on his site about setting the toe in.

I have put tape on the front surface of the tires and marked an X on each piece, then measure the distance between them. Then roll the car ahead until the x's are just below the frame so you can pull the tape across to measure. I've set the toe in so the rear measure is about 1/8" more than the front measure and this has worked well for me.

[Franchise_24]

We measured the back of the front tires and then the front of the front tires. It ended up being 1/4" toe in.

[Tom Wesenberg]

Originally Posted by Franchise_24

We measured the back of the front tires and then the front of the front tires. It ended up being 1/4" toe in.

You need to take measurements from the same spot on the tires to be accurate. If you measure the back, then the front, what about the wheel wobble and the tire tread that may be off? If each rim had only 1/8" bend, that alone can add up to a 1/4" wrong reading.

[Purdy Swoft]

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Originally Posted by Franchise_24

My question is 1/4" was the original spec. Would that *cause* it to shimmy?

The correct toe in is 1/16 plus or minus one 32nd . Too much toe in wouldn't cause shimmy. If it happened to be toed out at the front, the least bit it would cause shimmy. Any loosness anywhere in the front end, would contribute to the shimmy after it was set up.

I use a spring loaded telescoping measureing device purchased from a model a parts vender. I measure the toe in first at the rear of the wheel at the height, just under the wishbone, usually about 14 inches off the floor. With the measureing tool still in place, I push the car backwards untill the measureing tool rises to the same level in the front as it was in the back of the wheel when measured. It should be 1/16 closer at the front of the tire than the rear of the tire. It is difficult to acurately measure toe in with a tape measure and it takes two people. Setting toe in is a pain, I usually set it pretty close and drive it to a front end alignment shop and let them set the toe in.

[Franchise_24]

Originally Posted by Tom Wesenberg

You need to take measurements from the same spot on the tires to be accurate. If you measure the back, then the front, what about the wheel wobble and the tire tread that may be off? If each rim had only 1/8" bend, that alone can add up to a 1/4" wrong reading.

So basically Tom if I understand what you are saying correctly, you want to mark each tire and measure across. Then roll the car forward so it is at the same distance from the ground as it was before and measure again and that's how you figure the toe-in? Thanks!

[Tom Wesenberg]

Originally Posted by Franchise_24

So basically Tom if I understand what you are saying correctly, you want to mark each tire and measure across. Then roll the car forward so it is at the same distance from the ground as it was before and measure again and that's how you figure the toe-in? Thanks!

Yes, that's the layman's way to do it, and since it's at a larger diameter then Ford's way you will have a larger numer for the toe in. Maybe 1/8", where the way Ford and Purdy measured you'd have 1/16 + or- a little.

I've done it both ways, but just adjust my figures accordingly. The main thing is to take the tire tread and bent wheel out of the equation, Which is what Ford and Purdy have done, and I do by using tape with an X to measure both locations.

[Franchise_24]

Just a quick update. I know it's been awhile, and the car still shakes, but we may have narrowed it down to the steering box being the culprit. We are going to be taking it out eventually and checking it over, may be something as simple as a bushing, but we won't know until we get it out. I'll keep you all posted.

[Franchise_24]

Scratch my last post, we've actually decided after talking with some others we are going to replace the steering arms first before we mess with the steering box. The balls are a bit egg shaped so that was recommended to do. Hoping to do this on Thursday so I will let you know what happens.

[bogiediver]

Well?

Fighting much the same battle...

[Purdy Swoft]

A sagging front spring will cause front end shimmy .

[Franchise_24]

Bogie, I sent you a PM with my info.

[BILL WILLIAMSON]

Franchise,
Claude, my REAL GURU, has a knack for finding sometimes overlooked steering stuff. Even down to a SLIGHTLY loose nut that secures the steering arms to the spindles and with weight on the wheels and having a helper turn the wheels back & forth slowly & firmly while watching the action of the radius rod ball. A movement in the ball can literally "STEER" the car, causing wobbles, darting, etc. Make sure the steering gear is really tight to the frame as I have read that the holes were a little large so the gearbox can be tilted down to accomodate using a steering column drop block on Vickys & Phaetons. (I have one that drops the column by 1 1/2")
I asked Claude how he got so good at finding this stuff & he said, "From doing Factory Safety Inspections on Ford tractors. Starting from the steering wheel nut and working my way through the ENTIRE steering system, ending up at the wheel bearing adjustment & the toe in. Using a helper to turn it back & forth, & doing it with weight on the wheels." Also observe if there's any flexing in the frame rail at the steering box area! Bill W. ( And make sure it's not a funky TIRE problem!)

[Franchise_24]

Thanks Bill. Luckily I got the problem taken care of back in October. This is kinda an old thread that Bogie stumbled across, so I was just telling him I sent him a message directly about what all I did so if it helps lead him in the right direction then that is a win for me. Thanks for the advice. -Neal-

[BILL WILLIAMSON]

Originally Posted by Franchise_24

Thanks Bill. Luckily I got the problem taken care of back in October. This is kinda an old thread that Bogie stumbled across, so I was just telling him I sent him a message directly about what all I did so if it helps lead him in the right direction then that is a win for me. Thanks for the advice. -Neal-

Neal,
I didn't notice it was an old thread. Doesn't it make you feel GOOD when you win one!!
Glad I posted Claude's methods, it may help someone else.
I wish you knew Claude, he's a wealth of down to earth info, 86 years old and still bulding stuff. Our Sierra Chapter of MAFCA celebrated our 50th year tonight!!! Bill W.

[Franchise_24]

Congrats on the 50th Bill! Yes, it is good when you win one for a change!! LOL Now I just need spring to get here so I can drive it more haha

[Patrick L.]

A lot of time and energy went into this thread by everyone. Its nice to know what the problem was and what was done to correct it. Its pretty much a matter of common courtesy.

[bogiediver]

Here's my PM to Franchise_24 and his response... was going to do this yesterday and got distracted...
***********

Your last post was 9/18/12…

I’m having similar issues… was hoping I could persuade you to post an update to the thread…

Perhaps even a recap of all that you did and in what order…

Thanks for considering…

-bogie

Response:

There is no way I could narrow it down and say I did this and it fixed it. We spent MONTHS working on that front end and nothing seemed to work. To try to give a run down:

1) Replaced steering arms (both, balls were egg shaped)
2) Replaced bad tie rod end (other was fine)
3) Replaced guts on both ends of the drag link
4) Replaced guts on both ends of the tie rod
5) Used rubber ball and changed plate on the wish bone
6) All new wheel bearings and races for the front
7) King pins have been pulled - they have fairly new bushings that were reamed.
8) Tightened all perches and any castle nut under there.
9) Set the toe-in
10) Tried good tires from my Coupe on the Leatherback to rule out bad tires

All in all it was a combination of all that I believe. After I did all that in the list I still had the shake, so I ended up tightening the drag link arm even more to the point where it was actually recessed in the end and then the shake stopped.

Unfortunately I fixed it in early October and I live in Ohio so I haven't driven it much, but for all that I did drive through October I never had anymore shake, and I kid you not when I say I ran over ever bump and man hole cover I could to try to get it to happen LOL.

Let me know if you have any other questions and I can try to help.
*************

Neal - thanks for the reply...