Romadog wrote:

Make sure your spacers are Type Approved would be a good start otherwise your insurance maybe void

twopoint6khz wrote:

Assuming they're properly aligned they put no more stress on your bearings than wheels of the same offset, e.g. modulars. There are more nuts to come undone though.

jst wrote:

twopoint6khz wrote:

Assuming they're properly aligned they put no more stress on your bearings than wheels of the same offset, e.g. modulars. There are more nuts to come undone though.

true.

if you run spacers combined with a large offset rim then you can get bearing issues.

worse case is large offset, large tyre and then spacers. the further the load is from the kingpin the worse the effect on the bearings and scrub turn

Romadog wrote:

Make sure your spacers are Type Approved would be a good start otherwise your insurance maybe void

blackwolf wrote:

As stated above, wheel spacers won't affect your wheelbearings any more or any less than wheels with an equivalent changed offset. It is just another of those urban legends that they will.

Unless you opt for a very thick spacer or hugely different offset wheel, the increased loadings on the suspension components should be negligible.

The only aspect of the steering geometry that will be affected is the 'scrub radius', which is a function of the steering axis inclination and camber angle. The scrub radius is the distance between the point at which a line drawn through the centres of the top and bottom swivel pins instersects with the ground, and the line along which a plane through the rotational centre of the tyre intersects with the ground (which is generally outboard of the steering axis interstection point).

The scrub radius will increase if the tyre is moved outwards, either by use of a spacer or by use of a wheel with reduced (ie "more negative") offset. However, the scrub radius will decrease is a larger diameter tyre is fitted without changing the offset, since the act of raising the axle further from the ground will move the intersection point of the steering axis and ground plane outwards. Fitting a wider tyre of the same diameter to a wheel of the same offset won't affect the scrub radius at all, since the increase in tyre with is shared equally on either side of the rim.

The result of this is that fitting spacers and larger tyres will actually affect the steering geometry less than fitting spacers without fitting larger tyres.

The effect of increasing the scrub radius is that the vehicle will be more affected by changes and irregularities in the road surface; for eample, it may be more prone to 'tramlining' in lorry-ruts on motorways, more prone to a wobble when crossing white lines; that sort of thing. When I bought my 07 DC it had 285/75s already fitted on standard Boosts without spacers, and I fitted 30mm spacers as soon as I reasonably could (principally because the turning circle was unbelievable!). I found that the steering performance and handling improved afterwards.

One thing to bear in mind with spacers, especially thin ones, is that the hub/wheel interface may not be as strong as before, and this is probably the area of most concern (and the reason why spacers are not allowed in motorsport). For the spacer to work, the spacer must be bolted to the original wheelstuds and the the wheel bolted to studs fixed in the spacer. Therefore (a) the spacer must be of adequate strength/thickness to mount the new studs securely, and (b) the spacer must be think enough to accomodate the full length of the original wheel-studs AND the thickness of the nuts holding it to the original studs within the thickness of the spacer. With thin spacers, there is relatively little material left to secure the spacer after it has been counterbored to accomodate the nut. I don't believe that any reputable manufacturer makes spacers for LRs which are less than 30mm, and this is the reason.

There is no reason why any of the nuts should ever come loose. There is another urban legend that says the nuts should be threadlocked, but this is not a good idea. If the threads are kept clean with just a hint of copper-grease, and the nuts are torqued correctly, the nuts will not loosen.

Many insurance companies will frown upon the use of spacers and it is not clear why. It may be that they are too ignorant to understand them fully, or more likely they have stats whcih show that cars with spacers fitted are more likely to be involved in accidents than those without, which is probably true in the case of the Corsa-Kiddies but not 4WDs. A specialist insurer should be OK with them.

jst wrote:

good answer, very clear and informative.

Thanks! I try my best.

Martin H. Lee wrote:

Expect that the wheel spacer cause mechnical stress to wheel bearings, are there any safety issues related to wheel spacers?

Many thanks

Glad Blackwolf has confirmed what Matzker (German LR tuning specialists) told me
I have top-quality 3cm (each side) spacers and everything else standard (Boost with 235s).
The steering stops were adjusted and the turning circle is massively improved. I drive around underground car parks a lot, and the spacers mean I can park in (relatively) normal spaces. Look cool too
Without them, I scraped a few pillars with my "pillar sliders" and failed to park - very embarrassing
Matt Tell someone you love them today because life is short.
But shout it at them in German because life is also terrifying and confusing...