Isuzu N Series 2008 Owner's Manual page 431

2008N_sec07-2_print2.indd 85
SERVICE AND MAINTENANCE
11R22.5
(Standard tire)
265/60R22.5
(Low aspect ratio tire)
MFU770SH003401
Spare Tyre Air Pressure
Keep the air pressure of the spare tyre
slightly higher than the standard pressure.
Adjust the pressure correctly when you use
it.
Tyres heat up while driving, and their air
pressures become higher accordingly.
If you must wait until right after driving
to adjust the air pressure, determine the
target pressure for adjustment by adding
about 20 kPa (0.2 kgf/cm²/3 psi) to the
standard pressure.
Use of Low Aspect Ratio Tyres
Low aspect ratio tyres for truck applications
(aspect ratio at 70% or 75%) have an air
volume 20% to 30% smaller than that of
standard tyres. When air begins to leak,
therefore, low aspect ratio tyres adversely
affect vehicle operation much faster than
standard tyres. Check air pressure of low
aspect ratio tyres more often than standard
tyres using a tyre air pressure gauge.
Tyres Used for Long Term
Tyres are made of rubber whose property
changes gradually by aging as time goes
on (even when it is stored fitted on the rim
like a spare tyre). Tyres must receive an
aging check after being used for up to 5 to
7 years if they are to be used continuously.
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3/09/2008 5:53:26 PM