Still driveline vibration... help!!

Discussion in 'Trucks [ Eighteen Wheelers ]' started by JakeBrakeChampion, Mar 19, 2012.

  1. JakeBrakeChampion

    JakeBrakeChampion Light Load Member

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    I had my powerdivider completly rebuilt(it was shot) new u joint all the way to the transmossion and a new yoke on the backside of the carrier bearing and im still chasing a vibration. Symtoms are.... When in 8th gear (8ll transmission) Doing around 65 if you step anymore than half throttle you will get a chatter somewhere in the driveline if you coast it quites it. 7th gear has a constant rRrRrR then pause then rRrRrR and you can feel it right in the accelerator pedal. Others are low rpm chatter when your coming to a stop light in say 5th gear you will get a chatter very quickly if you no what im saying... Any ideas please and thank you!
     
  2. otherhalftw

    otherhalftw R.I.P.

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    Is it possible that the drive line is out of line with the connection point?
     
  3. truckmechanic

    truckmechanic Medium Load Member

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    Have you checked the trans drain plug for shavings where do you feel the vibration in the seat,shifter? Have you checked the rear suspension out for bad bushings, loose bolts, checked the height of the air bags, have you disconnected the drive line that goes to the 3rd axle and drove on the power divider to rule out a problem in the 3rd axle?
     
    otherhalftw Thanks this.
  4. truckmechanic

    truckmechanic Medium Load Member

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    Could also be in the clutch possibly starting to slip
     
  5. otherhalftw

    otherhalftw R.I.P.

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    Never mind what I said....go with what the mechanic says!:biggrin_25514:
     
  6. JakeBrakeChampion

    JakeBrakeChampion Light Load Member

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    No abnormal amount of shavings on the trans. Have had 3 diffent mechs adjust the clutch all 3 say it still looks brand new? Suspension is walking beams in the back so no air ride. Have not tried taking the 2nd driveshaft out. Also vibration mainly felt through pedals not much in seat or shifter and the noise does sound like its coming from the back but then again thats never accurate
     
  7. truckmechanic

    truckmechanic Medium Load Member

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    I work on a lot of mixers with walking beams check them carefully also check the tourqe arm bushings it dosent take much to throw the angles off I usually start off by turning the truck in a tight circle to see how far the rear axles are tracking I've seen bushings that look good but when you do this you can see the complete tire on the last axle past the first if your bushings are bad by chance don't replace them with poly bushings they don't hold up at all which suspension do you have
     
  8. JakeBrakeChampion

    JakeBrakeChampion Light Load Member

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    I dont no if it would be any indication but my dive tires always wear perfect. The rear suspension never seems to crack or bang like ive seen worn walking beams do. And by torque arms do you mean the ones that hold the rears in straight? That mount to the rears to the frame?
     
  9. truckmechanic

    truckmechanic Medium Load Member

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    Yes those are the tourqe arms
     
  10. truckmechanic

    truckmechanic Medium Load Member

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    Have you checked the motor mounts