Kimberley KARAVAN 2021, Installation, Maintenance & Operating Manual

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103 ©2021 Kimberley Kampers Manufacturing Pty Ltd
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Let’s face it: Wheel installation is
rarely viewed as a topic deserving of
much attention. Most shops tend to
zip them off, mount and balance,
and bang them back onto the vehi-
cle. Basically, wheels are considered
by many techs as components that
are essentially “in the way” when
performing other services such as
brake or suspension system jobs.
In reality, the wheels, and their
means of attachment to the vehicle,
are the most important components
on any vehicle. After all, if the
wheels fall off, it’s never a pretty
picture.
In this article, we’ll discuss the
basics of wheel fasteners and the
handling and proper installation of
alloy wheels, which deserve even
greater attention due to their higher
cost and because of the potential for
cosmetic damage.
WHEEL FASTENERS
Instead of referring to these all-
critical pieces (the only thing that
4
INSTALLING
ALLOY WHEELS
This is the correct method of installing any alloy wheel. Use a torque wrench, following correct torque
value and the proper criss-cross tightening pattern to avoid stressing or distorting the wheel or hub/rotor.
clamps the wheel to the hub) gener-
ically as “lug nuts,” get into the habit
of calling them “wheel fasteners,”
since that’s an apt description of
their task.
Also, although Toyota vehicles use
a threaded stud (affixed to the hub)
and a nut system to secure the
wheels, some vehicles feature female
threaded holes in their hubs and
require the use of wheel bolts. This
is just one reason to use the term
wheel fasteners to broadly refer to
any wheel-to-hub clamping system.
CHECK FASTENER SIZE
AND STYLE
Granted, when you remove an
original Toyota wheel and replace
the wheel using the same Toyota
nuts, you won’t have a nut-matching
problem. However, if you’re dealing
with a customer’s vehicle that fea-
tures aftermarket wheels, or have
been requested to change the
wheels from OEM to aftermarket,
never assume that you already have
the correct style of wheel nut. Check
to make sure that the thread size is
correct (shank diameter and thread
pitch), and make absolutely sure
that the fastener’s seat style matches
that of the wheels. Using an incor-
rect seat style will prevent secure
clamping of the wheel to the hub,
and will certainly result in loosen-
ing during operation. Packing/ship-
ping mistakes are always possible,
so never blindly assume that what
you have is correct.
Wheel fastener seat styles include
60-degree taper/conical seats,
radius (also called spherical or ball)
seats or mag-style straight shank
with flat washers.
Make sure that the new fasteners
match the seat style required by the
wheels at hand. Never mismatch by
using a mag/shank type fastener on
a wheel intended for a conical seat,
etc. Only the correct, matching type
seat will provide the required wheel
clamping. In the case of blind
(capped/enclosed) wheel nuts,
make absolutely sure that the nut
does not bottom-out against the
stud tip (this can occur if the nut is
too short for the application) This
situation will prevent full clamping
force, resulting in wheel wobble and
almost-certain failure of the thread-
ed studs.
Wheel fastener threads must be
clean and in good condition. Do not
lubricate threads unless specifically
instructed to do so by Toyota tech-
nical information specific to the
vehicle being serviced. Torque val-
ues are commonly specified based
on the use of dry threads. The use
of lubricants will result in over-
clamping and possibly stretching
the stud beyond its design yield
point.
UNDERSTANDING
THREAD SIZE
Fastener sizing involves selecting
the correct diameter, thread pitch
and length for proper thread
engagement. Following is a basic
overview.
DIAMETER
This refers to the diameter of the
threaded section of the fastener
(outer diameter of a bolt shank or
stud; or inner diameter of a nut’s
threaded hole).
Threaded fastener size is referred
to with a series of three numbers,
which indicate thread diameter,
thread pitch and shank length, in
that order. For example, a 1/2 x 20 x
4 indicates a bolt or stud that fea-
tures a 1/2-inch diameter shank, a
thread pitch of 20 (20 threads per
inch) and a shank length of four
inches. If the fastener is metric, the
numbers refer to the same dimen-
sional areas, but are indicated using
metric dimensions. For example, a
14 x 1.5 x 45 refers to a 14mm
T
O Y O TA’ S
S
U P P O R T
T
O
A
U T O M O T I V E
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E PA I R
INSTALLING ALLOY WHEELS
5
Fastener sizing cards are handy to determine bolt or stud diameter
(both inch and metric), as well as bolt or stud shank lengths and nut
diameters.