Vauxhall COMBO Owner's Manual page 156

Tread dept h
Check tread depth regularly.
Should the front tyres show greater wear
than the rear tyres, ha ve both front wheels
exchanged with the rear wheels so that the
tyres w ith deeper tread are on the front
axle.
Correct tyre pressure.
For reasons of safety, tyres should be
rep la ced when their tread depth has worn
down to 2 to 3 mm (winter tyres: 4 mm).
158
The leg ally permissible minimum trea d
depth (1.6 mm) has been reached when
the tread has worn down as far as one of
1 )
the wear indicators (TWI ). A number of
wear indicators are sp aced at eq ual
intervals around the tyre within the trea d.
Their position is indicated by m arkings on
the tyre sid ewall.
General i nformati on
z The risk of aq ua planing is greater if the
tyres are worn.
z Tyres age, even if they a re used only very
little or not at all. A spare wheel which
has not b een used for six years should be
used only in emergencies; drive slowly
when using suc h ty res.
1)
TWI = Tread Wear Indicator.
z Never fit used tyres the previous history
and use of which you do not k now.
z So as not to impair b ra ke cooling, use
only wheel trims approved for use on
your vehicle.
Tyre d esigna tions
Meaning s:
e.g. 155/80 R 13 79 T
155 = Tyre width in mm
80 = Aspect ratio
(ty re height to tyre width in %)
R = Belt ty pe: Radial
13 = Wheel d ia meter in inches
79 = Load ind ex
e. g.: 79 corresponds to 437 kg
T = Speed cod e
S peed code letters:
Q Up to 100 mph (160 km /h)
S Up to 112 mph (180 km /h)
T Up to 118 mph (190 km /h)
H Up to 130 mph (210 km /h)
V Up to 150 mph (240 km /h)
W Up to 168 mph (270 km /h)