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front end shake 34 pickup, help please

Discussion in 'The Hokey Ass Message Board' started by baddean, Jul 24, 2013.

  1. baddean
    Joined: Nov 26, 2012
    Posts: 44

    baddean
    Member

    ok I have a 34 pickup, every now and then I get a shake in the front end which is rather violent, I can even see the engine shake. but heres the thing no vibrations at any speed which eliminates out of round tyres, unbalanced etc, it feals as if the axle is hopping left to right, or up n down, it shakes the whole truck, but seams to do it at low speed, today turning left out of lights, maybe 1o mph or so.
    its running the buggy spring front, original oil shocks, 47 hyd brakes with the original wish bones split parallel back to the chassis, any idea what would be causing this??
     
  2. sr
    Joined: Feb 12, 2007
    Posts: 400

    sr
    Member
    from Monterey

    I have been trying to chase it down on my truck. Found many issues. Loose steering box. Fixed that it was good but then it happened again. So now i am going to do the easy things first.........Tie rod ends. Then King pins. Then spring bushings. Shocks. Wheel bearings are adjusted right. My friend in the military said just start replacing things until it is fixed! If you do to many things you never know what fixed it. Mine only shakes at low speed when one wheel hits a bump before the other. Then I have to put the brakes on HARD and it stops. Also looking at caster angles.
    So go through the list. Try one thing at a time.That is all I think I can do. Everyone has a different answer to the problem.
     
  3. baddean
    Joined: Nov 26, 2012
    Posts: 44

    baddean
    Member

    yes that is exactly the same thing and hitting the brakes seams to stop it, problem is everything on my front is new, although im suspecting a wheel bearing at this stage im looking into that tomorrow. I was thinking where the hub bolts to the I beam as well so il be jacking it up and looking into it, if I see anything ill repost a reply, but its defiantly a strange one as why wouldn't it do it a t high speed etc where it would be more prominent
     
  4. Do a search on " Death Wobble " guys , it's been covered many times here on the HAMB . :)



    .
     

  5. Y'all have "death wobble". My '29 A with a "suicide" front end has it. Not sure what causes it and there are more suggested reasons out there than you can count. I've tried all to no avail. I just live with it for now. Didn't notice it 'til I greased the front end. (Worn king pins?) But there seem nice and tight?
     
  6. AS above and try researching Kingpin Inclination,Camber and caster to see what make the front end tick. Some clear pics of your front end my show us clearly whats up. JW
     
  7. VoodooTwin
    Joined: Jul 13, 2011
    Posts: 3,455

    VoodooTwin
    Member
    from Noo Yawk

    I'm with JW^......I bet your caster angle is the issue. Show us close up pictures of your front suspension. Front and side views, to help us help you.
     
  8. bobby_Socks
    Joined: Apr 12, 2006
    Posts: 938

    bobby_Socks
    Member
    from ǑǃƕǑ

    There are alot of things that can cause this but from the desription that you give I would look at the shocks first.
     
  9. Fairlane Mike
    Joined: Sep 21, 2010
    Posts: 389

    Fairlane Mike
    Member

    Sure sounds like loose king pins, but try switching tires and wheels, see if that changes it any.
     
  10. Get a steering dampener from So-Cal Speed Shop or your local V-Dub guys. If it wont cure the problem, it will atleast get you going in the right direction. For about $40, that's where I'd start. Also, check your tires especially if you have bias-plys.

    Those 2 steps is where I'd start...
     
  11. All American 6
    Joined: Sep 25, 2012
    Posts: 234

    All American 6
    Member
    from Sumter, SC

    Here's the latest death wobble thread from the HAMB: Enjoy

    http://www.jalopyjournal.com/forum/showthread.php?t=804497


    The put on a damper vs fix your issues is worth the read.

    This is almost like the Seinfeld episode where George was parallel parking and he backed in with another car pulling in frontward. Half the people said it's ok to pull in forward. About half in my thread said it's ok to put on a damper before figuring out the cause of the shake problem.

    <object width="420" height="315"><param name="movie" value="//www.youtube.com/v/egsdc7tZ_xc?hl=en_US&amp;version=3&amp;rel=0"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="//www.youtube.com/v/egsdc7tZ_xc?hl=en_US&amp;version=3&amp;rel=0" type="application/x-shockwave-flash" width="420" height="315" allowscriptaccess="always" allowfullscreen="true"></embed></object>



    There are 23 threads on the HAMB with death wobble in the subject.
     
    Last edited: Jul 24, 2013
  12. junkman8888
    Joined: Jan 28, 2009
    Posts: 578

    junkman8888
    Member

    Greetings! Check your "Scrub Radius", for an explanation you can check "Wikipedia".
     
  13. lowelife
    Joined: Aug 30, 2007
    Posts: 400

    lowelife
    Member

    Make sure you check your connections at your wishbones. Check where they mount to the frame and kingpins. Found a problem there on my brothers "A" and it fixed the wobble.
     
  14. F-6Garagerat
    Joined: Apr 12, 2008
    Posts: 2,652

    F-6Garagerat
    Member

    Isn't a steering stabilizer just a band aid? If there's a problem I'd want to fix it. There's gotta be a reason he's got wobble. Find it and fix it.
     
  15. can be spring shifting side to side...panhard bar bushings...or go to dead perch...increase caster will make it turn harder but go down road straighter...
    seen it happen on new trucks..trackbar or panhard bar bushings go..whole frontend shakes ...scares the hell out of you first time ..lol...
     
  16. Ole don
    Joined: Dec 16, 2005
    Posts: 2,915

    Ole don
    Member

    If you have aftermarket wheels, that could be the problem. Stand way out in front of the truck and draw an imaginary line down through the king pin. Now do the same with the tire. The lines must meet at the ground. Re-read response number 12. Research that subject.
     
  17. I'd want it fixed the right way also...but for around $40 and a couple minutes of garage time, it is well worth it. Hell there are some shops that put out big $$$ rides, where the cars don't leave until they are absolutely 100% perfect that put these on EVERY car that goes through their shop because of the benefits they provide. My last 3 Hot Rods have all had them on and will continue to do so when the next one comes along..

     
  18. Yes,check your caster angle,I have my truck set at 7 degrees. HRP
     
  19. F-6Garagerat
    Joined: Apr 12, 2008
    Posts: 2,652

    F-6Garagerat
    Member

    I don't care who uses them, there's something wrong with his front end. Is it wise to install a part that will mask the problem? Something that could cause you to have some serious problems down the line. Do you get better speakers when your car is low on oil so you don't have to hear it knocking? Might get rid of the knocking sound but eventually it's gonna fry.

    I'll bet there are more cars that don't use steering stabilizers then there are cars that do.

    Oh, and did I mention they really look terrible on a traditonal hot rod?
     
  20. Fenders
    Joined: Sep 8, 2007
    Posts: 3,922

    Fenders
    Member

    Or you can use a 1960 - 78 VW steering damper, NAPA #113425021.

    If everything is tight, the cause is alignment. In my case correcting toe-in to 1/8" cured it.
     
  21. VoodooTwin
    Joined: Jul 13, 2011
    Posts: 3,455

    VoodooTwin
    Member
    from Noo Yawk

    ^ this x 2.

    Fix the problem, save the $40 for gas. My '33 truck drives great, no wobbles, no shakes, easy to steer.....and no stabilizer, no dead-perch, nothing added other than Henry Ford engineering and properly set up suspension geometry.

    Send us pix of your suspension and I bet we see the problem quickly.
     
  22. F-6Garagerat
    Joined: Apr 12, 2008
    Posts: 2,652

    F-6Garagerat
    Member

    That's all I'm sayin, if your front end is right it shouldn't need one.
     
  23. DICK SPADARO
    Joined: Jun 6, 2005
    Posts: 1,887

    DICK SPADARO
    Member Emeritus

    My take on this is that you have an induced low speed shimmy issue.

    This can be caused by a number of deficiencies in the front end starting with unequal tire air pressure, front end out of square or excessive caster angle. What is happening is the tire is excited to track in a straight line, hitting a bump or making a turn causes the tire to realign its direction slightly over rotating and then try and return to its normal position.

    This sometimes causes an over correction in the tire tread contact as the correction moment swings past its normal center as it tries to realign. This produces a shimmy effect until the oscillation is controlled by either speeding up or slowing down to allow the tire contact patch return to normal tracking.

    This can also be caused by excessively worn parts or bad steering adjustment but in most cases it comes from not squaring the spindles to the axle or having the axle skewed in installation position because the measurement tape was read incorrectly. The contact patch of both tires should be on the same lateral axis point not ahead or behind each.

    Step one is to even air tire pressure, step two is to square the axle and step threee is to check that the caster angle is between 4-6* top slanted rearward. Adding more caster will NOT solve the issue.
     
    Last edited: Jul 24, 2013

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