steering wheel CHEVROLET DYNASTY 1993 Manual Online

ponents. Under extremes of suspension and steering
travel tire damage may occur.
WARNING: FAILURE TO EQUIP THE VEHICLE WITH
TIRES HAVING ADEQUATE SPEED RATING CAN
CAUSE SUDDEN TIRE FAILURE.
ROTATION
DIRECTIONAL TREAD PATTERN TIRES
Some vehicles are fitted with special high-perfor-
mance tires having a directional tread pattern de-
signed to improve traction on wet pavement. To obtain the full benefits of this design, the tires
must be installed so that they rotate in the correct
direction. This is indicated by arrows on the tire
sidewalls. When wheels and tires are being installed, extra
care is needed to ensure that this direction of rota-
tion is maintained. Refer to Owner's Manual for rotation schedule.
NONDIRECTIONAL TIRES
Tires on the front and rear axles of vehicles oper-
ate at different loads and perform different steering,
driving, and braking functions. For these reasons,
they wear at unequal rates, and tend to develop ir-
regular wear patterns. These effects can be reduced
by timely rotation of tires. Rotation will increase
tread life, help to maintain mud, snow, and wet trac-
tion levels, and contribute to a smooth, quiet ride. The suggested rotation method is the forward-cross
tire rotation method. This method takes advantage of
current tire industry practice which now allows cross
rotation of radial-ply tires. Refer to the owner's man-
ual (usually found in the glove box) for additional in-
formation. Other rotation methods may be used, but
may not have all the benefits of the recommended
method. Always check air pressure and wheel nut tightness
after rotation. Do NOT use oil or grease on studs
or nuts. Refer to Owner's Manual for rotation schedule.
TREAD WEAR INDICATORS
Tread wear indicators (Fig. 3) are molded into the
bottom of the tread grooves. When tread is 1.6 mm
(1/16 in.), the tread wear indicators will appear as a
13 mm (1/2 in.) band. Tire replacement is necessary when indicators ap-
pear in two or more grooves, or if localized balding
occurs.
REPAIRING LEAKS
For proper repairing, a radial tire must be removed
from the wheel. Repairs should only be made if the
defect or puncture is in the tread area otherwise the
tire should be replaced. Deflate tire completely before dismounting tire
from the wheel. Use lubrication such as a mild soap
solution when dismounting or mounting tire. Use
tools free of burrs or sharp edges which could dam-
age the tire or wheel rim. Before mounting tire on wheel, make sure all rust
scale is removed from the rim and repaint if neces-
sary. Install wheels on vehicle, progressively tightening
wheel nuts to 129 N Im (95 ft. lbs.) torque (See
Wheels).
TIRE NOISE OR VIBRATION
Radial-ply tires are sensitive to force impulses
caused by improper mounting, wheel irregularities,
or imbalance. To determine if the tires are causing the noise or
vibration, drive the vehicle over a smooth portion of
highway at different speeds and note the effect of ac-
celeration and deceleration on noise level. Differen-
tial and exhaust noise will change in intensity as
speed varies, while tire noise will usually remain
constant.
TIRE WEAR PATTERNS
Under inflation results in faster wear on shoulders
of tire. Over inflation causes faster wear at center of tread.
Excessive camber causes the tire to run at an angle
to the road. One side of tread is worn more than the
other. Excessive toe-in or toe-out causes wear on the
tread edges of the tire, from dragging of tire. There
is a feathered effect across the tread (Fig. 4).
Fig. 3 Tread Wear Indicators
Ä WHEELSÐTIRES 22 - 3

WHEELS SERVICE PROCEDURES INDEX
page page
General Information ........................ 6
Tire and Wheel Balance .................... 6
Tire and Wheel Run Out .................... 7 Wheel Installation
......................... 6
Wheel Replacement ....................... 6
GENERAL INFORMATION
Original equipment wheels are designed for proper
operation at all loads up to the maximum vehicle ca-
pacity. All models use steel or cast aluminum drop center
wheels. The safety rim wheel (Fig. 1) has raised sec-
tions between the rim flanges and the rim well A.
Initial inflation of the tires forces the bead over
these raised sections. In case of tire failure the raised
sections help hold the tire in position on the wheel
until the vehicle can be brought to a safe stop. Cast aluminum wheels require special balance
weights and alignment equipment.
WHEEL INSTALLATION
The wheel studs and nuts are designed for specific
applications and must be replaced with equivalent
parts. Do not use replacement parts of lessor quality
or a substitute design. All aluminum and some steel
wheels have wheel stud nuts which feature an en-
larged nose. This enlarged nose is necessary to en-
sure proper retention of the aluminum wheels. Before installing the wheel, be sure to remove any
build up of corrosion on the wheel mounting surfaces
with scraping and wire brushing. Installing wheels
without good metal-to-metal contact could cause later
loosening of wheel nuts. This could adversely affect
the safety and handling of your vehicle. To install the wheel, position it properly on the
mounting surface using the hub pilot as a guide. All wheel nuts should be lightly tightened before progres-
sively tightening them in sequence (Fig. 2). Tighten
wheel nuts to 129 N Im (95 ft. lbs.). Never use oil or
grease on studs or nuts.
WHEEL REPLACEMENT
Wheels must be replaced if they:
² have excessive run out
² are bent or dented
² leak air through welds
² have damaged bolt holes
Wheel repairs employing hammering, heating, or
welding are not allowed. Original equipment replacement wheels are avail-
able through your dealer. When obtaining wheels from
any other source, the replacement wheels should be
equivalent in load carrying capacity. The wheel dimen-
sions (diameter, width, offset, and mounting configura-
tion) must match original equipment wheels. Failure to
use equivalent replacement wheels may adversely af-
fect the safety and handling of your vehicle. Replace-
ment with used wheels is not recommended as
their service history may have included severe
treatment or very high mileage and they could
fail without warning.
TIRE AND WHEEL BALANCE
Balancing need is indicated by vibration of seats,
floor pan, or steering wheel when driving over 90 km/h
(55 mph) on a smooth road.
Fig. 1 Safety Rim
Fig. 2 Tightening Wheel Nuts (5-Stud)
22 - 6 WHEELSÐTIRES Ä

HEATER-A/C UNIT ASSEMBLYÐREMOVAL AND
INSTALLATION
AP, AC, AY BODY PROCEDURE
WARNING: IF EQUIPPED WITH A/C, THE REFRIG-
ERATION SYSTEM MUST BE COMPLETELY EMPTY
BEFORE PROCEEDING WITH THIS OPERATION.
(1) Disconnect battery NEGATIVE cable.
(2) Drain radiator and disconnect heater hoses at
unit. Tape heater tubes to keep from leaking during
removal. Refer to Group 7, Cooling System. (3) Remove A/C condensate drain and disconnect
vacuum lines. (4) Inside passenger compartment, perform as fol-
lows, according to body designation. (a) AC-body, remove right upper and lower un-
der-panel silencers. (b) AP & AC-bodies, remove steering column
cover. (c) AC-body, remove left under-panel silencer.
(5) Position front seat or right front seat full rear. (a) AP-body, remove right A-pillar trim.
(b) Remove right cowl side trim.
(6) Remove glove box. (a) AC-body, remove right instrument panel re-
inforcement.
(7) AP-body only: (a) Remove right instrument panel lower mount-
ing screw. (b) Remove center bezel.
(c) Remove lower center module cover.
(d) Remove floor console.
(e) Remove instrument panel support brace (from
steering column opening to right cowl side at bot-
tom of instrument panel). (f) Remove instrument panel to support bracket
(below glove box opening). (g) Remove ash receiver.
(h) Remove radio.
(i) Remove panel top cover.
(j) Remove three right side panel to fence (below
windshield) attaching screws.
(8) AC-body, remove ash receiver.
(9) AP body, pull right lower side of instrument
panel rearward. (10) Remove center distribution and defroster
adapter ducts. (11) AP and AC-bodies, disconnect relay module.
(12) AP-body, remove instrument panel to unit
bracket. (13) AP-body, remove lower air distribution duct.
(14) Disconnect blower motor wire connector.
(15) Disconnect demister hoses from top of unit.
(16) For Non-ATC equipped vehicles, disconnect
the temperature control cable flag from the bottom of
the heater-A/C unit. Then un-clip the cable from the
left side of the heat distribution duct. Swing the ca-
ble out of the way to the left. Disconnect the vacuum
lines at the unit. (17) For ATC equipped vehicles, disconnect the in-
strument panel wiring from the rear face of the ATC
control unit. (18) AC body, disconnect right 25-way connector
bracket and fuse block from panel. (19) Fold floor right side carpet back (except AC
body). (20) From engine compartment, remove four unit
attaching nuts. (21) Remove unit hanger strap lower screw, and
rotate strap. (22) Move heater-A/C unit rearward to clear
mounting studs, and lower unit. (23) AP-body, remove demister adapter from top of
unit. (24) While pulling the lower right of instrument
panel rearward: (a) Slide unit upright from under instrument
panel for AP-body. (b) Except for AP-body, rotate unit while pulling
from under instrument panel.
To install, reverse the preceding operation.
Fig. 5 Blower Motor and Wheel Assembly
Fig. 6 Blower Wheel Retaining Ring Removal and Installation
Ä HEATING AND AIR CONDITIONING 24 - 61

AA BODY PROCEDURE
WARNING: IF EQUIPPED WITH A/C, THE REFRIG-
ERATION SYSTEM MUST BE COMPLETELY EMPTY
BEFORE PROCEEDING WITH THIS OPERATION. Refer to Group 8E and Group 23 for component re-
moval and installation when performing this opera-
tion. (1) Perform steps 1 through 7 of Blower Motor re-
moval and installation. (2) Remove relay panel above glove compartment
opening. (3) Disconnect the A/C vacuum line connector and
radio noise capacitor connectors. (4) Remove left windshield pillar trim cover.
(5) Remove left lower side cowl trim cover.
(6) Remove hood release handle mechanism attach-
ing screws. (7) Remove steering column trim covers.
(8) Disconnect parking brake release mechanism
connecting rod. Gain access through fuse panel open-
ing. (9) Remove lower left instrument panel silencer.
(10) Remove lower left instrument panel reinforce-
ment. (11) Remove instrument panel center (radio) bezel.
(12) Remove forward floor console.
(13) Remove the radio.
(14) Remove the heater-A/C control.
(15) Remove cigar lighter.
(16) Remove message center/trip computer, if
equipped. (17) Disconnect side window demister tubes from
top of heat A/C unit. (18) Remove steering column upper attaching bolts
and allow the steering wheel to rest on the driver
seat cushion. (19) Remove upper instrument panel (defroster
outlet) cover. (20) Remove upper instrument panel attaching
screws from below the windshield opening. (21) Loosen (do not remove) the left lower cowl in-
strument panel attaching screw. (22) Remove the right lower cowl instrument panel
attaching screw.
CAUTION: Protect the passenger seat cover from
soiling or damage using a suitable cover.
(23) Carefully pull the right side of the instrument
panel away from the vehicle. Allow the instrument
panel to rest on the passenger seat cushion.
CAUTION: Before proceeding with the next opera-
tion, review the Safety Precautions and Warnings at
the front of this Group. (24) From the engine compartment, drain the cool-
ing system and disconnect the heater hoses from the
heater core nipples. Plug the nipples to avoid spilling
coolant inside the vehicle. (25) Disconnect the refrigerant lines from the ex-
pansion-valve at the dash panel on the right side of
the vehicle. Seal the refrigerant lines to prevent con-
tamination. (26) Remove the expansion valve from the evapo-
rator plate. Seal the valve to avoid contamination. (27) Remove the condensate drain tube.
(28) Remove heater-A/C unit to dash panel attach-
ing nuts. (29) From inside the vehicle, pull rearward on the
heater-A/C unit to clear the dash panel silencer and
remove the unit from the vehicle. To install, reverse the preceding operation. Refill
cooling system and test for leaks. Evacuate and
charge the refrigerant system and test overall perfor-
mance.
AG, AJ BODY PROCEDURE
WARNING: IF EQUIPPED WITH A/C, THE REFRIG-
ERATION SYSTEM MUST BE COMPLETELY EMPTY
BEFORE PROCEEDING WITH THIS OPERATION.
(1) Disconnect the battery negative cable.
(2) Drain the coolant from cooling system. Refer to
Group 7, Cooling System. (3) Remove the air conditioner expansion valve (if
equipped). (4) Disconnect the heater hoses from heater core.
Then plug or cap the tubes on heater core. This will
prevent spilling coolant into the interior of vehicle
during unit removal. (5) Remove the condensate drain tube.
(6) Disconnect the A/C-heater vacuum supply line
from vacuum supply nipple (in the engine compart-
ment). (7) Remove the four A/C-heater assembly-to-dash
panel attaching nuts. (8) Remove the passenger side front seat. Refer to
Group 23, Body. (9) Remove the kick panel/sill cover at right door
opening. (10) Remove the body computer (Fig. 6) located at
the lower right section of the right front door pillar. (11) Remove the glove box assembly. Refer to
Group 8E, Instrument Panel. (12) Remove the carpeted panels from both sides of
the console. (13) Un-clip the radio antenna cable from the
metal support (Fig. 6) located behind and below the
glove box opening. (14) Instrument panel removal is not necessary to
remove the A/C-heater assembly from the vehicle.
24 - 62 HEATING AND AIR CONDITIONING Ä