Suspension/ handling issue 2015 prostar

Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by Taylorla03, Oct 21, 2019.

  1. Taylorla03

    Taylorla03 Bobtail Member

    3
    0
    Oct 21, 2019
    0
    I have been having an issue with my truck for months. While driving at highway speeds it has a shake that can be felt through the steering wheel. The steering wheel has a tremble and it does feel like the steers shake. It drifts/ wanders. I feel like it has excessive drift and looseness as far as how much control I have of the truck.
    I have had 2 alignments, replaced the kingpins, replaced bushings for the kingpins, u-bolts, bearings, replaced front steers and balanced. I might've had some other minor things done but it hasn't really made a difference or it was ok for a couple of days and then came back. It also sometimes pulls to the side when braking. I've put a lot of work into this truck but I'm considering walking away. Any suggestions would be greatly appreciated. Thanks
     
  2. McMahons Trucking

    McMahons Trucking Light Load Member

    212
    83
    Jul 4, 2018
    0
    Have you had the spring bushings checked? Tire balance checked?
     
  3. Frontman

    Frontman Light Load Member

    100
    80
    Apr 4, 2012
    NORTH MS
    0
    What kind of drive tires are you running?

    'pulls to the side when braking', maybe that brake to too tight.
     
  4. VWbeagle

    VWbeagle Bobtail Member

    10
    6
    Dec 21, 2016
    0
    Hopefully when they were doing your king pins they checked to see if the axle eye where the king pin goes through wasn’t worn out like an egg. Sometimes they need to be drilled and sleeved. So if the pins were replaced and the axle eye is not round it will have a wonder like a loose king pin. Pulling when braking is usually one side is set tighter than the other. Check the adjustment on the brakes and make sure they are working the way they should.
     
  5. Taylorla03

    Taylorla03 Bobtail Member

    3
    0
    Oct 21, 2019
    0


    Makes a lot of sense. If this is the case would the kingpins need to be replaced again? I know it needs another alignment. Thanks a lot for the info.
     
  6. Taylorla03

    Taylorla03 Bobtail Member

    3
    0
    Oct 21, 2019
    0
    Yes, I had the tires balanced when I bought the steer and I was told the bushings were good. Thanks though.
     
  7. Heavyd

    Heavyd Road Train Member

    6,723
    4,587
    Feb 4, 2009
    0
    If the steering wheel shimmies at highway speeds, you have a steer tire or wheel out of round or out of balance. You need to get the wheel spin balanced on the truck. This checks for out of round or off center wheels.
     
    spsauerland Thanks this.
  8. AModelCat

    AModelCat Road Train Member

    13,543
    51,198
    Jul 7, 2015
    Republic of Western Canada
    0
    I'm not an alignment guy by any means but what about the caster? Not enough caster can give the front end kind of a twitchy feeling.
     
    Taylorla03 Thanks this.
  9. VWbeagle

    VWbeagle Bobtail Member

    10
    6
    Dec 21, 2016
    0
    If they were done very recently, you might be able to reuse the king pin kit. Only if there is no damage to the pin itself, and everything comes apart fine. Quick check would be lift up the front end one side at a time and check the king pins. Everything should be tight, if there’s movement anywhere get a light bulb and have a closer look to see where it’s coming from.
     
    Taylorla03 Thanks this.
  10. FreightyAK

    FreightyAK Bobtail Member

    25
    20
    Aug 7, 2018
    AK
    0
    How are your drums? Warped or OOR brake drums are commonly overlooked when diagnosing shakes. That wont explain the wandering of the front. Also check your draglink and steering box. You might be surprised how a worn steering box can make the truck feel.
     
    Taylorla03 Thanks this.
  • Draft saved Draft deleted