Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Help! Hard Braking Problem! Suspension related I think!

Discussion in 'The Garage' started by Pookster, Jan 15, 2004.

  1. Pookster

    Pookster 1/2 ton status

    Joined:
    Nov 21, 2000
    Posts:
    3,195
    Likes Received:
    0
    Location:
    NYC, NY, USA
    Here's what happens:

    Under hard braking in less than ideal conditions (Snow, ice, etc). in 4wd, all 4 wheels can lock up-

    However, the truck loads up like a spring! and it is worse from one side to the other, so that the passenger seems to compress more than the drivers side, and as such , the truck will start diving toward the right.

    My assumptions:
    1. The diving of the truck causes more friction for the tire to grab, hence forth the fact that under hard braking, the truck will acutally try and spin itself around.

    2. It is not bump steer related- The effects are the same whether I am holding onto the steering wheel or not.

    Ok, other issues, which may/may not be related-

    In 4wd, at 35mph, the accelerator can make directional changes, - MEaning that if I am on the gas, then get off of it, the truck wants to change directions. Hit the gas again, and it changes back. Is there a relationship?

    I dont think my 208 is worn but could tha thappen? Just seems like the rear wants to give more ooomph than the front.

    SEtup: 87 k5, 4" lift, echobit rear, 1.5" relocation in the the rear, ORD brace, ORD swaybar disco, new gear box, new PS pump, new tie rod, joints, etc,new body mounts, new VST shocks
     
  2. yunit

    yunit 1/2 ton status

    Joined:
    Feb 24, 2000
    Posts:
    3,068
    Likes Received:
    0
    Location:
    Oakland, NJ
    What is your rear brake setup like? When I had rear drums, the truck would dive to the passenger side; because of a bad cylinder. Once I gave up on the bad rear brakes & warped drums and went to disc's in the back, my truck would brake straight & smooth.
     
  3. Pookster

    Pookster 1/2 ton status

    Joined:
    Nov 21, 2000
    Posts:
    3,195
    Likes Received:
    0
    Location:
    NYC, NY, USA
    Strange, but I guess it could be related-

    it is drums in the back, but the drums and pads are 1 year old (and I took them off to check it). The thing is, the symptoms Im expericing is when all 4 wheels are locked on a slippery surface (such as snow).

    I would imagine that with all 4 wheels locked it really doesnt make that much difference whether they were drums or discs.
     
  4. lukebaby1

    lukebaby1 1/2 ton status

    Joined:
    Dec 16, 2003
    Posts:
    231
    Likes Received:
    0
    Location:
    Richmond, Virginia
    I would take a look at your swaybar tricks, and could be front or rear springs flexing. May need some type of ladder bar setup to minimize spring torsioning. Also check front and rear frame to spring anchor points for play. /forums/images/graemlins/shocked.gif /forums/images/graemlins/thumb.gif
     
  5. rawkrash

    rawkrash Newbie

    Joined:
    Nov 21, 2003
    Posts:
    2
    Likes Received:
    0
    I suspect that it actually may be "bumpsteer" related.

    I just did a 4" lift on my suburban and it exhibits a little of the same behavior.

    As the front suspension compresses, the truck goes one way and as it extends, the truck goes the other.

    The reason is that I haven't corrected the steering geometry for the lift yet. The short draglink that the GM push-pull steering system uses can cause some significant bumpsteer even with lifts as short as 4 inches.
     
  6. Pookster

    Pookster 1/2 ton status

    Joined:
    Nov 21, 2000
    Posts:
    3,195
    Likes Received:
    0
    Location:
    NYC, NY, USA
    My thoughts too- however, by letting go of the steering wheel, you are letting the suspension and drag link follow its desired path- it will move your steering wheel for you.

    this is more of a suspension compression issue I think. I do recall asking MR. Watson about how the sway bar disconnect system should be installed- I tihnk one of my bolts is too tight, causing movement in an incorrect area.

    Im just trying to work out all the theories first, so I only have to crawl under the truck once. Its getting a mighty bit Nippy out... -10 dropping to -25.

    The snow isnt even compressing. its kinda like... soft powder. its real slippery, even my friend's truck with blizzaks are having a tough time from doing the sideway dance.
     
  7. az-k5

    az-k5 1/2 ton status

    Joined:
    Oct 15, 2003
    Posts:
    2,774
    Likes Received:
    0
    Location:
    Phoenix AZ
    If there is a slight difference in breaking from side to side, even a responce of fractions of a second, it can cause your truck to kick a little. I had a dually flat bed that loved that game. Hauling 2 pallets of tile at 60, lock it up oops, now were not in our lane anymore or the one next to us for that matter. Just a thought.
     

Share This Page