Tiffin Motorhomes Allegro Bus 2011, Руководство пользователя

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R O U T I N E M A I N T E N A N C E
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Additionally, underinflated tires will also cause poor handling of the motor home, rapid and/or
irregular tire wear, and an increase in rolling resistance of the motor home which, in turn, produces a
decrease in fuel economy of operation.
An overinflated tire will reduce the tire’s “footprint” (i.e., its actual contact with the road); thus,
reducing the traction, braking capacity, and handling of the motor home. A tire that is overinflated
for the load that it is carrying will also contribute to a harsh ride, uneven tire wear, and the tire itself
will be more susceptible to impact damage.
Maintaining correct tire pressure for each loaded wheel position on the motor home is critically
important and must be a part of regular vehicle maintenance.
Tire Maximum Load Rating
Federal law requires that the maximum load rating be molded into the sidewall of the tire. If one looks at
a tire sidewall, one may see some “
typical ” information, such as:
Max. Load Single 3640 Lbs at 85 psi cold
Max. Load Dual 3415 Lbs at 85 psi cold
The maximum load allowed for the size tire and load rating and the minimum cold air-inflation pressure
needed to carry that stated maximum load are noted on the tire. Using less air pressure would reduce the
load-carrying capacity of the tire.
The amount of air pressure one needs depends on the weight of
the fully loaded motor home. Consequently, one cannot determine the correct air-inflation
pressure, unless one knows the actual weights of the motor home
.
Weighing the Motor Home
Earlier, in Chapter 1, the procedures for weighing the motor home were presented (see pp. 1-7 and 1-8).
These procedures provided the weighing of an “unloaded” (i.e., not stocked with the possessions and
provisions the user would normally have onboard for travel) motor home. Obviously, any additional
weight stored onboard (inside and underneath) the motor home will contribute to the overall weight of
the motor home.
If not stored uniformly throughout the motor home, additional weight of the possessions and provisions
of the motor-home user will load each axle and each tire differently (front-to-rear and side-to-side
distribution of that additional weight). Accordingly,
it is necessary to weigh the motor home fully
loaded as the user would have it for travel, including occupants. Moreover, it is necessary to
weigh each tire position individually .
Overloading the motor home can produce problems with the tires, wheels, springs, brakes, drive train,
and other motor home assemblies. In addition, an overloaded motor home uses more fuel, is more
difficult to handle properly, and can lead to driver fatigue more quickly. In a worst-case condition, if any
component should fail, this could result in loss of control of the motor home and subsequent damage.