odd clunking sound from the rear

Discussion in 'Engine & Transmission' started by BrissyGeorge, May 22, 2018.

  1. BrissyGeorge

    BrissyGeorge Active Member

    Messages:
    241
    Location:
    Brisbane
    I have a speed related clunking sound from the rear -esp at low speeds. It doesn`t happen when I move off but after a moment of movement it starts ........clunk clunk clunk .......... getting faster and louder as the road speed picks up, The clunk can be felt throughout the ute. ITS NOT THE ENGINE for those that were busting to make the obvious dak dak jokes about the noise of a VW engine:)

    I know a noise is hard to define (and diagnose) without hearing it but what are some of the options - ie if CV joints are on the way out, what sort of noise do they make.

    To make it even harder, it doesn`t happen all the time, however its starting to happen more frequently and is starting to get really loud. Most times it will stop after a while.

    Please help.
     
  2. Barry

    Barry Well-Known Member

    Messages:
    2,342
    Location:
    Abbotsford NSW
    I will go for the do-nut on the torsion bar

    Especially if it is rhythmic and speed related

    If the rear torsion has an "open end" holding plate - Have a look and see if the torsion bar is in the centre of the plate or up the top
     
  3. Barry

    Barry Well-Known Member

    Messages:
    2,342
    Location:
    Abbotsford NSW
    Piece 2 is the covered end - you wont be able to see

    But the do nuts are pieces 3

    upload_2018-5-22_16-10-1.png
     
  4. cbus

    cbus Well-Known Member

    Messages:
    10,646
    Location:
    sunshine coast
    Get logical.
    Jack up each side ,taking usual precautions of stands and chocks, and turn each rear wheel.
    Give a yank on them as well
    Sounds like really bad CV.
    Probably bolts loosened.?
    Check wheel nuts first while on ground.
     
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  5. BrissyGeorge

    BrissyGeorge Active Member

    Messages:
    241
    Location:
    Brisbane
    Barry,

    Piece 2 is the covered end - If I remove this what should I be looking for?

    Cbus

    Wheel nuts are tight.

    There is a little in and out play on each wheel - maybe 1-2mm..The shafts don`t have any rotational movement but move in and out as they should (I assume).

    All bolts on the 4 CVs are tight BUT both inner CV boots have holes
     
  6. Wayne murray

    Wayne murray Well-Known Member

    Messages:
    1,503
    Location:
    Seven hills
    If the CV boots have holes there is more chances the grease is gone and water can enter,possible starting point. Other area is rear wheel bearing.
     
  7. cbus

    cbus Well-Known Member

    Messages:
    10,646
    Location:
    sunshine coast
    The in .out play sounds normal.
    They are not a tapered bearing.

    Longitudinal movement on shafts is normal.
    Assume out of gear and handbrake off when checking rotational play.?

    Surprised no play. Usualy a touch.
    Hence suggest double check that.

    Boots will need replacing to keep crap out.
    Small cuts might be glueable if cleaned well and superglue ??

    With wheels raised rotate each and listen.

    Does it appear mechanical or could it be a bulged tyre.
    Although I would expect that at very low speeds as well.
     
  8. Mellow Yellow 74

    Mellow Yellow 74 Active Member

    Messages:
    771
    Location:
    Sydney
    This is like a really weird poem
     
  9. cbus

    cbus Well-Known Member

    Messages:
    10,646
    Location:
    sunshine coast
    :D
    Or....
    " my teenage years in a kombi" ??
    :eek:
     
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  10. Grantus

    Grantus Well-Known Member

    Messages:
    13,917
    Location:
    Southern ACT
    Sounds like the CV’s will need attention, when you have the time and the money.;)
    ,
     
  11. Barry

    Barry Well-Known Member

    Messages:
    2,342
    Location:
    Abbotsford NSW
    Is the noise occur in a straight line or going around a corner?
     
  12. BrissyGeorge

    BrissyGeorge Active Member

    Messages:
    241
    Location:
    Brisbane
    Straight line - I understand what you are trying to determine - wheel bearings if it was round corners and perhaps would be more of a grumbling than a rhythmic clunking?

    I will check though whether it changes going around a corner
     
  13. Barry

    Barry Well-Known Member

    Messages:
    2,342
    Location:
    Abbotsford NSW
    CV's in my experience make most noise going around corners

    If the do nuts are shot then the torsion bar will be hitting on the tube
     
  14. Mordred

    Mordred Super Moderator Staff Member

    Messages:
    2,626
    Location:
    Penna, Hobart
    I am still thinking CV's. The fact it is speed dependent and no changing with lateral force in a corner and stops from time to time. Lack of grease means it may move a little in and out of the worn area and stick in each position for a while. Can't hurt pulling them out and inspecting and greasing them. That way you eliminate them from this problem and also give them a service.

    Adrian
     
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  15. Barry

    Barry Well-Known Member

    Messages:
    2,342
    Location:
    Abbotsford NSW
    and it is a shite load easier than changing the do-nuts o_O
     
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  16. cbus

    cbus Well-Known Member

    Messages:
    10,646
    Location:
    sunshine coast
    Easy to check the outer one tho.
     
  17. BrissyGeorge

    BrissyGeorge Active Member

    Messages:
    241
    Location:
    Brisbane
    Well, I took a punt and went for the CVs - replaced all 4 - quite an easy job - about 3 hours from jack stands to test drive.

    Unfortunately the test drive wasn`t long enough to be conclusive as the noise was intermittent but if it comes back I can at least cross CVs off the list. One of the CVs fell apart when I slid it off the axle so it was pretty worn I guess

    I`ll drive for a couple of days and let you know if the clunk is gone
     
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  18. Mordred

    Mordred Super Moderator Staff Member

    Messages:
    2,626
    Location:
    Penna, Hobart
    I reckon that would be your candidate there. Job well done, good luck.

    Adrian
     
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  19. lachie

    lachie Member

    Messages:
    162
    Location:
    terranora
    Don't throw away your old cv joints- I found after replacing mine with new vw stamped ones i had a failure within about 1k- and was very glad to have the original Dobro spares to put back on.

    The cooling fan can make an occasional "Tardis" sound- related to engine speed if it has gone out of balance- better to discover that early rather than late.
     
  20. David H

    David H Well-Known Member

    Messages:
    2,860
    Location:
    newcastle
    Perhaps Lobro ;).

    What grease did you pack them with?

    Good move as that one that 'fell apart' was so close to :mad:. Good job:).

    Cheers
     

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