Engine Systems

The transmission includes an electrically controlled power take off

(PTO). The PTO provides power to a hydraulic pump, which powers the

vehicle's hydraulic system.

The hydraulic system operates the self-

recovery winch, the material handling crane, the heavy duty recovery

winch, and the pumping equipment, depending on how the vehicle is

equipped.

(c) Transfer Case. The transfer case (3) (figure 16 on the previous

page), connects the drive train to the No. 1 and No. 2 axles when 8-

wheel drive is needed.

The transfer case has two gear ratios (high

and low) and neutral.

Because the gears are not synchronized, the

vehicle must be stopped before the transfer case can be shifted

between ranges.

Engagement of the transfer case in low range will

automatically engage the drive train to the front axles.

(d) Tandem Axles and Suspension. The front and rear-tandem axles (4)

are of the single reduction, full floating axle shaft type. The front

tandem provides steering. The rear tandem is nonsteering. Both front

and rear tandems are equipped with wheel differentials and interaxle

differentials.

The interaxle differentials have driver-controlled

lockouts for positive drive to all axles in low range.

The rear

tandem is equipped with permanently engaged controlled traction

differentials. The front and rear suspensions are of the tandem axle

type, with leaf springs and equalizer beams.

(e) Propeller Shafts and Universal Joints. The propeller shafts and

universal joints (5) transmit engine power to the axles.

(2) Engine Systems. In the following subparagraphs, we will discuss

the subsystems that comprise the engine system.

(a) Air Intake System (figure 17 on the following page).

The air

intake system consists of a dry type air cleaner (1), turbocharger

(2), engine blower (3), and an aftercooler (4). Engine exhaust gases

flow through the turbocharger,

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