Results 1 to 10 of 10

Thread: weird tyre wobbles at 70kph

  1. #1
    jbe's Avatar
    jbe is offline Master Silver Subscriber
    Join Date
    Nov 2015
    Location
    Yass
    Posts
    248
    Total Downloaded
    0

    weird tyre wobbles at 70kph

    I have a weird tyre shake issue at around 70kph +-10% which has got me perplexed.


    About five weeks ago, I noticed a lot of play in my steering box and decided to get it replaced. However, I had no noticeable tyre shake or wobbles on my Defender 110 at this point in time.

    When I picked the car up from the workshop with the new steering box fitted, I noticed for the first time that it had a bad tyre shake at around 70kph, but no issues above or below that speed. It can be clearly felt on the steering wheel and the issue just happens at this speed and doesn’t seem to be caused by bumps in the road (which would make me think worn bushes).


    First, I thought that maybe the wheel nuts might be loose, but they were tightened properly.

    Later that week, I checked all suspension links, steering linkages, tierods swivel hubs and wheel bearings for play and all bolts and clamps involved as well. There was nothing obvious.

    Then, I swapped my wheels back to front, but the problem persisted.
    I also changed the panhard rod bushes as the old ones have been through a desert trip last year with a lot of corrugations. Still no luck with the tyre shaking issue.


    Given that my Nittos were on their way out with 5mm tread left, I decided to get new KM3s fitted. However, even with brand new and properly balanced wheels the problem is still there.
    I wouldn’t call my tyre shake bad, but is still noticeable and medium annoying.

    I was thinking that it could be the steering damper. So, I pulled it out and it feels firm in center position.

    I haven’t checked the rims for runout and my control arm bushes look fine. I also haven’t pulled the shocks out yet for inspection as the feel fine.

    My Defender runs 35” tyres with -25 offset rims. The car has a bot 4” lift and I did a Discovery pitman arm conversion not too long ago (well before the issue emerged).


    So, my questions are:
    - Is it at all possible that a new (refurbished) steering box brings out an old/existing underlying problem and/or amplifies it?

    - Has anyone come across similar issues?
    - Where next to look??

    Cheers Joachim

  2. #2
    Join Date
    Apr 2016
    Location
    Melbourne
    Posts
    4,203
    Total Downloaded
    0
    Quote Originally Posted by jbe View Post
    ......

    I was thinking that it could be the steering damper. So, I pulled it out and it feels firm in center position.

    .....
    This bit reminds me of the classic Who song ... 'we won't get fooled again'

    I had a similar, but different, issue a while back.
    I got a Pedders steering damper couple of year prior. Not my first choice but with the timing no other option.
    Anyhow, fitted it and ran for two years.
    I also changed panhard bushes and bolts(always do the bolts too), plus other sundry bits that needed doing, tie rod ends, drag link(a bit dodgy) .. etc.

    Pulled the stg damper, felt perfectly fine in the centre as you said too. had a mil or two of slack at both extremities, but the steering doesn't actually travel that far.
    Did wheel bearings. no change.

    My issue was tho that under no power but hitting a bump where both fronts at the same time would cause not just a steering wobble, but a death wobble, starting at about 70k/h
    Hit bump on one wheel, nothing.
    But if I hit the same 'join in the road' with both fronts under power, I'd get no wobble!(made no sense to me)

    Anyhow, changed the steering damper bushes, old ones were fine, but thought what the hell.. had to try something.
    Made a very small difference .. so I thought at least I'm almost on the right track.

    So got a std steering damper(they're Armstrong branded), to replace the what seemed fine Pedders damper, came with new bushes, but use the poly bushes I got previously replaced .. and no matter how hard I try to cause the previous death wobble, she just won't do it now.

    Still have the old Pedders stg damper in a box .. thinking to try to re-fit it to see if it's just a badly made item, or something else had changed.

    On my old RRC, I reckon I must have replaced quite a few worn std steering dampers(>600k Klms tho), I did once get a Koni damper as it was there and cheap enough.
    I didn't feel it made any difference, and I can't remember it being either better or worse in terms of longevity, so all subsequent stg dampers were just the cheap as chips standard types.

    Hope this info is of some help.
    Arthur.

    '99 D1 300Tdi Auto
    '03 D2 Td5 Auto

  3. #3
    Join Date
    Mar 2008
    Location
    Outer Sydney
    Posts
    478
    Total Downloaded
    0
    Hi Joachim,

    I had a similar wobble. It eventually got bad enough that when hitting a bump i would get the death wobbles. I rebuilt the swivel housings and it fixed the problem. Recently i started getting a similar wobble again (without the death wobbles). I found the very slightest amount of play in the swivels. I took one shim out and it solved the wobble. I don't know what the new preload was, but it felt 'about right'. (From memory it is meant to be 2 - 4 kg?). You might not have any play in your swivels, but perhaps the preload is too low.

    Edward

  4. #4
    jbe's Avatar
    jbe is offline Master Silver Subscriber
    Join Date
    Nov 2015
    Location
    Yass
    Posts
    248
    Total Downloaded
    0
    Thanks for the responses.The weird thing is that the issue is caused solely by speed, no bumps involved. I'll have a good look at the steering damper and if that doesn't make a difference, I'll have another look at the swivels. The weird thing is that I can't feel any play on the wheel nort south and east west when jacked up. This convinced me (for now) that the wheel bearings and swivels are fine.

  5. #5
    Join Date
    Dec 2006
    Location
    Torres Straits
    Posts
    3,471
    Total Downloaded
    0
    Is it possible the “new” steering box is a Britpart or other such quality unit and has a little play in it?

    My first guess would be swivel pre-load BUT running your lift and 35s if the swivels were wonky chances are you would have felt the wobbles before steering box changebover

    Wobbles can be frustrating as they are usually the result of multiple worn components and harmonics.

    S

  6. #6
    jbe's Avatar
    jbe is offline Master Silver Subscriber
    Join Date
    Nov 2015
    Location
    Yass
    Posts
    248
    Total Downloaded
    0
    Quote Originally Posted by roverrescue View Post
    Is it possible the “new” steering box is a Britpart or other such quality unit and has a little play in it?

    My first guess would be swivel pre-load BUT running your lift and 35s if the swivels were wonky chances are you would have felt the wobbles before steering box changebover

    Wobbles can be frustrating as they are usually the result of multiple worn components and harmonics.

    S
    No, it is a refurbished box with some improvements, I bought from a supplier here in Aus. I usually test for play in the front at the wheel and could not detect anything in any direction which made me think everything is fine. I might take the drag link off and double check the pitman arm directly. The steering box feels fine to me.

  7. #7
    discorevy is offline ChatterBox Silver Subscriber
    Join Date
    Nov 2014
    Location
    Nirvana near Albany W.A.
    Posts
    2,356
    Total Downloaded
    0
    X3 for swivels
    You need to drop off the track rod / drag link to check properly.
    If they want to self centre or are not smooth through the arc you'll need to replace the bearings
    If they're smooth but loose , do the shims

  8. #8
    JDNSW's Avatar
    JDNSW is online now RoverLord Silver Subscriber
    Join Date
    Jan 1970
    Location
    Central West NSW
    Posts
    28,804
    Total Downloaded
    0
    With the suspension modifications you mention, it will not take much to wobble. While its starting with the box change may be coincidence, my first thought would be that the box has play in it, or its mounts are loose (or cracked) or the pitman arm is loose on the box. If all that checks out, I would look at the swivel preload - it is possible that the new box has less friction than the old, and this was enough to pass the tipping point, and you can regain control with a small increase in drag at the swivels.
    John

    JDNSW
    1986 110 County 3.9 diesel
    1970 2a 109 2.25 petrol

  9. #9
    jbe's Avatar
    jbe is offline Master Silver Subscriber
    Join Date
    Nov 2015
    Location
    Yass
    Posts
    248
    Total Downloaded
    0
    Great feedback all :-). Today, I took the wheels, drag link and trackrod off.

    - the swivel hubs move fine and there is no play or flat spot detectable.
    - all tierod ends on the trackrod and drag link are in good order and pivot in any direction with the same resistance and no play.
    - the pitman arm shows no movement/play on the sector shaft.
    - the steering box has about 1mm play at the end of the pitman arm in diagonal direction, but no up or down play.
    - there is no noticeable play on the steering wheel after everything was reassembled.

    As for the diagonal play on the pitman arm: should it be completely tight, or can it have some play like I described?
    I think, I ring the shop where I purchase the box form on Monday to have a chat about this issue.

    Cheers J

  10. #10
    Join Date
    May 2006
    Posts
    459
    Total Downloaded
    0
    I once had a wobble with Defender 130 that took me a long time to figure out. Probably not what causing problem that Joachim is having though. Annoying vibration at 90 -100 kph. Wheels were 6.5 inch wide tubeless Wolf type rims with 2.35 /85 X16 Goodrich Mud Terrains. I had bought them secondhand a fair while before Interesting point but maybe irrelevant to the story that numbers on them did not include Land Rover part unless the 'genuine' ones were different regarding the important point. Former owner said apparently they had been imported into Western Australia and originally sourced from the factory that supplied the same rims to Land Rover.

    As the treads were getting down somewhat, thought it worth having wheels rebalanced as have come across ones that got out of balance as they wore. This did not fix it. Anyway, eventually figured out the problem. Have found that tubeless tyres sometimes develop intermittent leaks when they get old and worm. When they do, I usually have had a tube put in rather than trying to reseal the bead properly. Had a local tyre place that was under somewhat mediocre management at the time do this. Problem was what they did. These tubeless Wolf lookalike rims had half inch hole for the teat. On my tubed Wolf rims it was five eights of an inch. They had put a tube with a teat to fit the large hole into rim with small hole. It poked through enough to pump up etc. The apparent cause of the vibration problem was that around the teat, the tube was not contacting the rim. It was balanced on a dynamic balancer. However, I gather these normally spin at equivalent of a not very fast road speed. Maybe 30 km/hour. It seems that when the speed is increased, the part of the tube not seated would move due to centrifugal force. So what was balanced at low speed was unbalanced at high speed.

    One option would have been to replace the tube with one with a small teat. However, I drilled out the hole in the rim to the standard larger size. and put the same tube back. Problem cured! One lesson I learnt re drilling hole in steel rim out is to take the tyre right off beforehand and carefully clean drilling swarf away. I only takes the tiniest piece of this to cause a later slow leak type puncture.

Tags for this Thread

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Search AULRO.com ONLY!
Search All the Web!