Tiffin Motorhomes 2014 Allegro Owner's Manual page 111

TIFFIN MOTORHOMES
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,
Figure 13-6. Rear Tires
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:
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.
–ALLEGRO®
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.
Max. Load Single 3640 Lbs at 85 psi cold
Max. Load Dual 3415 Lbs at 85 psi cold
!!!
Chapter 13 ROUTINE MAINTENANCE
Figure 13-7. Front Tires
13-24