
by Alain Hoffmann
Wheel wobble and how to cure it
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Wheel wobble or judder is present on each of the coil-sprung Land
Rovers. Some 90/110's have it to a lesser degree, astoninglisly.
Normally it is felt as a judder in the steering wheel not unlike
the one you feel when your tires are out of balance. It can go on
for a very long time and worsen to the point the car is almost undriveable.
The causes are easy enough to correct so there's no reason to drive
like that. I took a recent article in LRO as a base for writing
this as it inspired me to do that job on my own car.
In 90% of the cases it can be brought down to Swivel bearing worn.
The other possibilities are discribed following their likeliness.
1. Worn Swivel Bearings
The Swivel is the large chromed ball you see when you look under
your car near the outer ends of the front axle.
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This chromed ball has an upper and lower bearing that
allows your wheel to turn. The bearings located inside this ball may
wear which is quite normal. Extensive wear, however, is an MOT failure
in most countries. Luckily you can quite easily adjust them. They
need a little force on them to work properly and keep the wheel steady.
If they wear they gain just a bit more space to "jump" up
and down, reducing the maintaining force of the wheel considerably. |
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Left: This is where the lower bearing sits... |
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Right: ... and here's the upper bearing located. The force on the
bearings is generated by shims (red arrow, below) placed under the
locating pin. Or let's say shims are placed under NEW bearings and
taken out when the bearing wears.
It's quite an easy task to adjust this. You need, apart from the
usual tools an torque wrench, an simple spring loaded balance and
I'd recommend an steering joint puller.
Jack up the vehicle after chocking the wheels. Feel for movement
by pushing/pulling on the top of the wheel. Remove the wheel.
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Now remove the steering joints, 2 on passenger side wheel, one
on the drivers side. Use the special puller to push them apart.
Don't use a hammer if possible.
Left: This one's from Facom, the famous french manufacturer. It's
quite expensive but I have it for about 10 years now and it cracked
every joint I could trow at it. Note that I always leave the nut
on for better grip and added safety.
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Now that the swivel pivots freely connect the spring balance to
the arm (green arrow). Try to get a reading of the required force
to move the arm. You should get values around 12 lbs or 6 kgs for
an new one. You are likely to get values nearer to 0 however.
So remove the upper 2 bolts (number 6) after having hammered down
the safety tap. Now fiddle with brake lines and mud shield until
you can separate them. Now you have access to the locator pin (E).
Note which way it's turned before removing it. For moving put a
sturdy screwdriver under it and gently push it up. Oh, I forgot:
Put a bucket under it as some oil will escape.
Once the pin out you will have a small pack of shims in your hand.
If there are no shims under the pin it means your bearings are worn
beyond use. Get new bearings and a shim pack.
Start by halving the thickness of the shim pack, then put everything
up together again. No need to fiddle with the brake lines yet, just
leave them out of the way.
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Bolt down the pin again, evenly. Use the torque wrench to bolt
them down to 60-70Nm/44-52lbs/ft. Check this value first in your
maintenace book if you don't trust me. Lower pin bolts only need
22-28Nm. Work your balance again on the arm (green arrows) to see
if you're right. The factory says to set them at 6 kg/12 lbs, some
prefer to set it at 8kgs/16 lbs for a more precise feel.
Once you achieved the correct value you remove the 2 bolts, clean
them, put the brake line holder and the locking tab under them and
bolt everything together. It's about half an hours' work if you
do it the first time. Repeat this on the other side.
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