Road Wheel And Tyre Balance; Road Wheel Nut Torque Tightening - Aston Martin V8 Vantage Workshop Manual

Misalignment Effects
Misalignment
Road wheels are correctly aligned
but crabbing due to road camber
Shows road wheels 'Toed-out' in
motion
Shows road wheels 'Toed-in' in
motion
Alignment Precautions
The following alignment precautions should be observed:
1. The vehicle should have come to rest from a forward
movement. This ensures, as far as possible, that the road
wheels are in natural running positions.
2. It is preferable for alignment to be checked with the
vehicle laden (Refer to 'Specifications', page 4-1-2).

Road Wheel and Tyre Balance

Static Balance
For smooth riding, precise steering and the avoidance of
high speed 'tramp' or 'road wheel hop', all tyres are balance
checked to predetermined limits. To ensure the best degree
of tyre balance, the covers are marked with yellow spots on
the outer sidewall and these indicate the lightest balance
point of the cover.
The original degree of balance is not necessarily maintained.
It can be affected by uneven tread wear, tyre removal or
refitting, by road wheel damage or eccentricity. The vehicle
may also become sensitive to imbalance due to normal wear
of moving parts. If roughness or high speed steering troubles
develop and mechanical investigation fails to disclose a
possible cause, road wheel and tyre balance should be
suspected.
If balancing equipment is used to dynamically balance
road wheels, always jack both rear road wheels off the
ground when rear road wheel balancing, otherwise
damage may be caused to differential. This is doubly
important in case of vehicles installed with a limited
slip differential, as in addition to possible damage to
the differential, the vehicle may drive itself off the jack
Dynamic Balance
Static imbalance can be measured when the tyre and road
wheel assembly is stationary. There is another form known
as dynamic imbalance which can be detected only when the
assembly is revolving.
There may be no heavy spot, i.e. there is no natural
tendency for the tyre and road wheel assembly to rotate
about its centre due to gravity, but the weight may be
unevenly distributed each side of the tyre centre line.
Laterally, the eccentric road wheels give the same effect.
During rotation, the offset weight distribution sets up a
situation which tends to steer the road wheel to the right and
left alternately.
October 2005
Effect
All tyres will wear
equally.
RH front tyre will
wear faster.
LH front tyre will
wear faster.
Warning
or stand.
Dynamic imbalance of the tyre and road wheel assemblies
can be measured on suitable tyre balancing equipment, and
corrections implemented. Where it is clear that a damaged
road wheel is the primary cause of severe imbalance, it is
advisable for the road wheel to be renewed.

Road Wheel Nut Torque Tightening

Repair Operation Time (ROT)
Item
Road Wheel
Order - Tighten every
second nut until all
five nuts are
tightened.
Tighten all road wheel
nuts in two stages.
1. To 80Nm (60 lb. /
ft) in one
continuous
movement.
2. To 135Nm (100
lb. / ft.) in one
continuous
movement.
Inform the customer that the wheel nuts are to be torque
Workshop Manual
Road Wheels and Tyres (04.04)
checked after 32km (20 mile).
Suspension (04.00)
Code
(LHF) 04.04.AB
(RHF)
04.04.CB
(LHR) 04.04.BB
(RHR)
04.04.DB
4-5-7