PREVOST GKN AXLES LIMITED KIRKSTALL DIVISION, Руководство по обслуживанию

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Section 16: SUPPLEMENT INFORMATION ON INDEPENDENT FRONT SUSPENSION (IFS)
16-22
4.5 Toe-In Check
1. Check the camber adjustment and adjust
if necessary.
2. Hoist the front of the vehicle and spin the
wheels marking the centerline of the tire
treads.
3. Place the wheels in the straight ahead
position and bring the vehicle to rest on
the floor.
4. Roll the vehicle ahead several feet. This
removes any slack caused by looseness
in the wheel bearings or steering connec-
tions.
5. Check the distance between the tire
centerlines at the front and rear of the
front tires. These two measurements
must be made at the same height above
the floor. The front measurement must be
3/32 ±1/32 of an inch less than the rear
measurement.
4.6 Toe-In Adjustment
1. Disconnect the drag link from the bell
crank.
2. Loosen the tie rod clamp bolts.
3. Using a pipe wrench, turn the tie rod
tubes to obtain the toe-in measurement
specified in step 5 under paragraph "4.5
Toe-in Check" of this Supplement.
4. Tighten the tie rod clamp bolts and re-
check toe-in.
5. Check that the angular relationship of the
pitman arm to the steering gear is as
shown in figure 7.
6. Adjust the drag link to mate with the bell
crank and install the drag link.
Note:
Use only tie rods to adjust toe-in.
4.7 Front Axle Caster
Positive caster is the inclination of the king
pins toward the rear of the vehicle. Negative
or reverse caster is the inclination of the king
pins toward the front of the vehicle. This vehi-
cle is designed with positive caster. The pur-
pose of caster is to provide steering stability
by keeping the wheels in a straight ahead
position.
Caster variations may be caused by bent
upper suspension arm, lower suspension
arm, or king pin housing. Caster can not be
adjusted. Incorrect caster must be corrected
by replacing the damaged suspension parts.
Precision instruments should be used to
measure caster.
Variations from the specified caster will affect
steering stability, cause wandering, wheel
shimmy, and reduce returnability when pulling
out of curves.
4.8 Major Damage
If the suspension has major damages, it may
be necessary to shim the bell crank and the
idler arm to avoid the bump steer or roll steer.
Moreover refer to paragraph "4. Front End
Alignment".