Wicked steering wheel shake, straight axle, found some issues with my setup...

ALL FIXED 8/26/12 check page 4


Took the Nova out for its maiden voyager

Roads in WI are shit and I almost shit myself, I hit a few nasty bumps and my steering wheel started shaking pretty nasty.

I used to ride motorcycles, we called it " Tank Slap " and the fix was a Stabilizer, well shooting the shit with a guy at this car show mentioned an episode on stacey davides Gearz about a fix, searched and found what he used...

My question for those in the ' Know ' what is the best one to buy, SO-CAL speed shop sells one http://www.est1946.com/steeringdamper.aspx

Everything on my car is Quality so I would like to purchase the best stabilizer because

Thanks much !!!

Update 2 hrs later

Shook the front end down and right away felt play, I was paying attention to the steering wheel input shaft, when I wiggle the front end the steering wheel input on the steering box doesn't move...

For certain I clamped it with vise-grips and I had an easy 1/4 of play witch is huge..

You can clearly see its rocks back and forth as if the bearings are SHOT, there are also a few drops of oil near it. I'm buying a new one, but before I buy a new one here are some pictures of my setup, after reading a bit I hope my pitman arm is not to radical of a drop.

Also found out with the help of google my steering box is a saginaw GM, the part # is 7809666 on the case. I personally do NOT know if I can convert to a Flaming Rivers, I only use that as an example because I see it recommended due to the quality...







FRONT SHOT


REAR SHOT

Update : 7/29

After a ton of reading and positive thinking I started at the steering box, this box is a saginaw if that matters, well as I noted it was very loose.

Ended up removing the steering wheel shaft and drag link, loosened up the adjusting nut and follow some DIY dirrections, slowing going back and forth with the easy of my finger tips I found just enough adjustment via the screw on top of the steering box.

Shook it down and there is so very little play, much much better.

2nd I marked my dash with tape, centered wheel and kept going right and left until I found center. 2 1/4 turns left and right.

Hooked up my drag link and found my rims NOT pointing straight, adjusted each tie rod end so that both rims were 52 1/4 front and back. I will have a shop go over it for sure, my settings are just getting as close as I can get

I did everything on Jack stands, tightened everything up jumped in the car and kept going back and forth. World of difference just by the feel, there is no binding at all. Only point where it gets slightly snug is the center on the steering box.

Here are some more pictures I took today, one thing I think I should do with the help of the HAMBS recommendation and just simply looking at it and studying it is to remove those 2" aluminum blocks. I will have to re-locate the shocks to the axle itself...
















Little update 8/13/12 :

Car was picked up today, right away he told me what was wrong and will be removing the " aluminum block, flipping the axle and setting proper caster...

We briefly talked about caster, he gave me some insite and mentioned 5-6 degrees is typical for the race car chassis he builds for top end the car forces itself to drive straight....

Shocks will be mounted straight up and down, reading the instructions from speedway they recommend straight up and down or a maximum tilt to the back of 5 degrees. I'll stick with what straight up and down

Speaking of caster, what value or determination goes into figuring out caster on a straight axle ?

I will also be getting full 3" stainless exhaust on the car including ( 2 ) cutouts for when I want to make some noise....

Whats nice is that I'm 100% worry free of this shops work, he was just featured on a Twin Turbo Mach 1 build that flat out shows his quality and I think just pure Love for cars...

Thanks so much guys...

 

Something is very likely worn or not adjusted correctly. Steering stabilizers just mask an underlying issue. Check your rod ends, ball joints, etc. You'll likely find something worn and loose causing the "death wobble"

 

Loose parts,steering geometry.Whats your caster setting?Do a search for "death wobble" You'll find a wealth of information on this subject in a number of other posts.

 

Thanks for the heads up, this kit was not fabricated by myself, all of the parts are new, but that doesn't account for the miles the previous owner put on, so really they are used

I'm just getting into straight axles so I will have to research on the death wobble..

My vega steering box is set up as " cross steer "

The wobble mainly came from the passenger wheel, I will be going over all of the rod ends and ball joints...

" Death Wobble is right " wasn't expecting that

I agree as I do not see them as the " Norm " thanks for the info !

 

Shackle angle is very important on a cross steer with out a panhard bar.

 

If it was a transverse front spring. I would guess his Nova has parallel spring setup.

But, yes, can't hurt to look at the shackles to make sure they don't have side slop.


If he knows it's coming from one wheel, I'd think he will find it pretty quickly...whatever it is. But like was said before, check caster also.

 

had the same problem on 36 in avatar, steering stabilizer fix it . it was cheap too pete& JAKES had it 30$

 

I used the SoCal stabilizer. It made a world of difference.

 

Make sure you have enough positive caster,then ck for worn parts.

 

VW bug, really cheap and at local stores...

 

Updated : I added new info to my 1st post...

Put her up on jack stands and gave her a shake down, a shake down I never gave as everything is so new.

But....

I have a feeling the steering box was used, I just do !

By running the casting #'s on google its a Saginaw box, Saginaw I'm guessing was the OEM for many 60's chevys ?

http://www.jegs.com/i/Borgeson/153/920027/10002/-1

Jegs sells what leads me to believe an exact replacement of what I have, tomorrow I will double check the mounting holes...

I'm not Brand aware for some of this stuff, Borgenson decent ?

 

Steering box needs to be centered when wheels are straight ahead.

Take off the drag link. Count the turns from lock to lock at the steering wheel. get the wheel exactly, exactly in the center of the travel.

Now see how close the drag link is to fitting back on with the wheels exactly straight ahead. Even a 1/4" off here will make a big difference. This needs to be right. adjust drag link.

Frank

 

Its tough to see in the pictures but does that axle have any kingpin inclination? and what is the caster set at?

 

I swear by Borgeson parts. Everything I have ever purchased from them is top notch! http://www.borgeson.com/

 

I live about four miles from the Borgeson factory......Took a tour of their plant at one of their open houses.They are state of the art and real great people.I have always used their products.

 

With the car on the ground can you shake it side ways any side to side movement of the axle with a cross steer is trouble.

 

While probably not the cause of your Death Wobble, I'm not a big fan of riser blocks on a front axle....

I would verify your caster at the kingpins is a minimumof 6 deg, some say you can go as much as 10 deg. Not having this caster in your geometry will cause death wobble....

I'm also wondering if the riser blocks are letting your axle "shift" too much.....meaning are the blocks possibly letting the axle "swing" under the springs, changing the caster slightly? Make sure those bolts are tight.

Tom

 

Yeah...blocks on the front axle are generally frowned on and usually illegal if spotted in a roadside check.

GASPUMPER is dead on...gotta center the box and adjust the crosslink to allow it to remain centered when going straight down the road. The box has a tighter area right at the center for stability and also to allow for adjustment/wear.

That IS a lot of drop on the pitman arm...and the crosslink still isn't level.
Maybe the steering arm at the spindle can be rebent?

4x4's with a big drop on the pitman arm will often use a tubular steering box stabilizer bracket...basicly a tube brace that runs from the right frame rail over to a flat metal clamp that bolts tightly around the box just above the pitman arm location.
Keeps the box from flexing on its mount and eventually tearing out in offroad use, but obviously would take out minute flex and tighten up the steering feel in normal use.

Personally I see no issues with a hydraulic steering stabilizer being used on cars as a handling aid...but you DON'T use it as a BANDAID!
Cure the problem first!

 

Looks way wrong to me, because it's so hidden. The scrub radius being way out can be the cause of death wobble, or the trigger to set it in motion with worn parts.

Scrub radius: The imaginary centerline of the king pin, where it intersects the road, under the tire. If your line is way inboard of the tire, you may be forced to use a heavy duty damper if you don't want to build a decent front end.

Scrub is very often ignored on many builds I see. Adding discs really throws it out, then add the wrong offset wheels.... It all puts so much more loads on all your steering components.

 

My first questions usually center around , Did you check for loose parts or excessive play in any connection joints including the steering box and axle U bolts? Since everything is basically new but the steering box the first place to look is the condition of the box wear. Other poster have mentioned this too. If your steering box is not adjusted correctly or excessively worn issues will easily develop.

The next step is to determine the angle caster of the axle, positive (meaning the top tips rearward) with a starting point around 4-6 * and no more. This must be checked at ride height and should read the same on both axle bosses.

Following a caster check the next check is a toe check. Do this by first disconnecting the tie rod and drag link, then by using a small carpenter square, square each spindle so they are at a right angle to the axle tires facing straight ahead, reattach the tie rod and adjust if necessary. Now using a tape measure and the inner side wall of the tire at 3 and 9 o'clock positions set the toe in to no more than 1/8", this means the distance measure at the front edge is smaller than the distance at the rear edge by 1/8" and tires point inward at the front. Tighten the tie rod adjustment and hook up the drag link, readjusting if necessary. Set the tire pressure evenly at 24lbs and take you car for a test drive to see if the problem reappears and re post.

 

I had a shimmy that was hard to find until I measured the wheel base on each side of the car. I found out that there was 1/2" difference. That ended my front end shake problem

 

I just wanted to share with you that I had a straight axle front suddenly "got crazy" on me. I was literally "tacking" like a sailboat to stay between the paddle markers. The final analysis? King pins. Take a look. It may not be your problem but don't overlook it. Once you hit something you didn't intend to at road speeds it may you last action.
Normbc9

 

Awesome info....

Blocks will be removed, I was actually going to remove them regardless, dropping it that extra 2" will look better but 1st off all minuses out all types of flex. When I first bought this car I looked at those and thought " Yikes those bolts better be quality "

Thank you

 

had the same issue with mine & it got worse as the springs broke in so i had to change the angle a couple degrees & now i have driven it a ton & no woble. also steering return is still good & no stabilizer is installed. i think it is at 7 degrees positive caster/tilted rearward at the top is where we ended up to make it happy. or coarse this is on a 55 chevy with the front & rear axles about 3" forward from stock with a bbc motor. hope this helps.

 

While not a cause of death wobble, don't over look your toe in. Same for Ackerman. Would be wise to google some real definitions for the suspension geometry/alignment terms. Going in half cocked could be dangerous. Best to have some education so you know what your looking for/at.

Not saying you don't know, but I haven't seen you respond to some others comments that are right on.

 

Jaws your right, this is one thing I'm light years from, Geometry and myself never got along throw in suspension and I need help, luckly I Have some good friends and good selection of hot rod shops near me

Toe in and tow out I understand, and I'm adjusting it as we speak, just taking a dinner break.

So far TODAY I centered the steering box, found center taped the dash and went left and right until it was pretty much 2 1/4 turns for each side, hooked up drag link and yep things don't look straight.

I also fixed the Steering Box Play to so very little, I ended up removing the steering wheel rod and the drag link per request on .net instructions...

I could move the steering box just by finger tips, center would tighten up and smooth up after center. Tightened up steering box and I hope its not Shot as I jumped to thinking that !

So right now I'm just going to measure rim to rim and try to get it exact, or 1/8 toe in based off recommendations. But will take it to an alignment shop for Exact fitment

 

Hi there, been reading you problem wit the death wobble and there is a car club in Mn. that does a lot of straight axle installs and did two tri five cars with early chevy pickup axles. I read those blogs for like months before I attempted mine. one thing I read over and over was that you drag link must be paralell with the front axle to prevent bump steer and such. Also the caster topic comes into play. I notice with those lift blocks and sitting on the stands with the weight of the car on them your drag link has a severe upward angle between the pitman arm and the steering link. I believe if you removed those lift blocks your drag link will fall right inline with the plane of your axle. I stayed on that when building my 55 and it drives like a dream. Kinda like an old pick dream.lol. Also redid the king pins before the build. Hope this helps, take care,cool car. YRUHOT.......Doug

 

Yruhot.....

Thanks for the info, yes the drag link sure does go up on an angle even with the pitman arm being already at least 3" drop, if those blocks were out it will be pretty dam close to being inline with the axle....

Close picture show's you how the blocks are installed

 

could be the picture but it Looks like the axle is mounted upside down.
The scrub angle is way off , should at least hit halfway into the tire.



Double check the caster also, 6-9 degrees ussually works.

.

 

It certainly does look that way. If it is, stop, and fix that first. If that is the case, it would make for a very uncomfortable handling situation.

We all make mistakes. I've done worse.