Dodge 2008 Ram 2500 PowerWagon - Manual (Page 84)

POWER WAGON FEATURES
Locking Front and Rear Differentials
Most 4WD trucks are equipped with open differentials
front and rear. This design is used because it allows each
wheel to turn independently helping to eliminate bind-
ing when cornering. A disadvantage of using an open
differential is when one or more wheels lose traction; all
of the power is directed to those wheels resulting in a loss
of momentum. The Power Wagon is equipped with
electronically locking front and rear differentials. These
differentials, when engaged, mechanically lock together
the axle shafts forcing the wheels to spin at an equal rate.
This allows the vehicle to maintain its momentum and
thus prevents it from becoming stuck. The locking front
and rear differentials should only be engaged during
low-speed, extreme off-road situations where one wheel
is likely to not be in contact with the ground. It is not
recommended to drive the vehicle with the differentials
locked on pavement due to the reduced ability to turn
and speed limitations.
4.56:1 Gears
This is the highest axle ratio available in a full-size
pickup. The high gearing helps to compensate for the
increased rolling mass and increase diameter of the
off-road tires. As well, there are many advantages to a
higher axle ratio in off-road applications. When driving
downhill the high gearing enables the driver to use the
engine to slow the vehicle down in a more controlled
manner. When driving up a steep grade, the ratio helps
by keeping the truck in its power band helping to
maintain upward momentum.
84 UNDERSTANDING THE FEATURES OF YOUR VEHICLE