Steering System - OD16150043

Introduction to the High Mobility Multi- Purpose Wheeled Vehicle HMMVV
Page Navigation
35

system comprised of the following components:

steering wheel, steering

gear, power steering pump, hydro-boost, lines, steering column, steering

linkage, tie rod, center link, idler arm, and pitman arm.

The turning

effort at the steering wheel is transmitted to the steering gear where it is

hydraulically multiplied and transferred to the front wheels through the

steering linkage.

a. Components of the Steering System. In the paragraphs that follow,

each of the components comprising the HMMWV steering system will be

discussed.

b. Steering Wheel. The steering wheel is a three-spoked, 15 1/2 inch

steering wheel with a center-mounted horn button.

It is secured to the

upper steering column with a hex nut.

c. Steering Column.

The steering column is a two-piece assembly

consisting of an upper steering column and an intermediate steering shaft.

The two pieces are universally-jointed and the intermediate shaft is also

splined to the steering gear stub shaft and secured with a bolt through the

slip yoke.

d. Power System.

The power system is composed of the steering gear,

power steering pump, and interconnecting hoses.

The fluid supply is

maintained in a reservoir mounted on the power steering pump. The pump is

operated by a drive belt mounted on pulleys attached to the pump shaft and

the engine crankshaft.

The power steering system on the HMMWV holds one

quart of Dexron II hydraulic fluid.

The gearbox used in an integral power steering system is basically a manual

gearbox adapted to include a power assist package.

The integral power

steering gearboxes are of two types: offset and inline. However, since the

HMMWV uses the offset or recirculating ball bearing type of gearbox, that is

the only one that will be discussed in this text. The offset type uses a

recirculating ball-