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5-2
BRAKES
wheel brakes at low pressure with initial brake application.
The low pressure fluid quickly provides the displacement
requirements created by the seal retracting pistons into the
front calipers and spring retraction of the rear drum brake
shoes.
O P E R A TIO N OF DISC BRAKE
Upon application of the brakes, fluid pressure behind
the caliper piston increases. Pressure is exerted equally
against the bottom of the piston and also against the bottom
of the piston bore. The pressure applied to the piston is
transmitted to the inner shoe and lining, forcing the lining
against the inner rotor surface. The pressure applied to the
bottom of the piston bore forces the caliper to slide or move
on the mounting bolts toward the inner side, or toward the
vehicle. Since the caliper is one piece, this movement toward
the vehicle causes the outer section of the caliper to apply
pressure against the back of the outer shoe and lining
assembly, forcing the lining against the outer rotor surface.
As line pressure builds up, the shoe and lining assemblies are
pressed against the rotor surfaces with increased force,
bringing the vehicle to a stop.
Lining wear is automatically compensated for by the
outward movement of the caliper and piston. Brake fluid fills
this void as lining wears.
O PER A TIO N OF C O M B IN A T IO N V A LV E
The metering or hold off section of the combination
valve limits pressure to the front disc brakes until a pre
determined front input pressure is reached, approximating
the pressure to overcome the rear shoe and lining retractor
springs. There is no restriction at inlet pressures below 21
kPa (3 psi) to allow for pressure equalization during non
apply periods.
The proportioning section of the combination valve
proportions outlet pressure to the rear brakes after a pre
determined rear input pressure has been reached. This is
done to prevent rear wheel lock-up on vehicles with light
rear wheel loads. Certain models having high rear wheel
loads do not have the proportioning feature.
The valve is designed to have a "By-Pass" feature
which assures full system pressure to the rear brakes in the
event of a front brake system failure. Full front pressure is
retained in the event of rear failure.
The pressure differential warning switch is designed to
constantly compare front and rear brake pressure from the
master cylinder and energize the warning light on the dash
in the event of a front or rear system failure. The valve and
switch are so designed that the switch will latch in the
"warning" position once a failure has occurred. The only
way the light can be turned off is to repair the failure and
apply a pedal force as required to develop up to 3100 kPa
(450 psi) line pressure.
DIAGNOSIS
IN SPEC TIO N A N D TESTING BRAKES
T esting Brake s
New linings must be protected from severe use for
several hundred miles.
Brakes should be tested on dry, clean, reasonably
smooth and level roadway. A true test of brake performance
cannot be made if roadway is wet, greasy or covered with
loose dirt so that all tires do not grip the road equally.
Testing will also be adversely affected if roadway is crowned
so as to throw weight of vehicle toward wheels on one side or
if roadway is so rough that wheels tend to bounce.
Test brakes at different vehicle speeds with both light
and heavy pedal pressure; however, avoid locking the wheels
and sliding the tires on roadway. Locked wheels and sliding
tires do not indicate brake efficiency since heavily braked
but turning wheels will stop vehicle in less distance than
locked wheels. More tire-to-road friction is present with a
heavily braked turning tire than with a sliding tire.
External C o n d itio n s th a t Affect B rake Perform ance
1. Tires—Tires having unequal contact and grip on road
will cause unequal braking. Tires must be equally
inflated and tread pattern of right and left tires must be
approximately equal.
2. Vehicle Loading—When vehicle has unequal loading,
the most heavily loaded wheels require more braking
power than others. A heavily loaded vehicle requires
more braking effort.
3. Front Wheel Bearings—A loose front wheel bearing
permits the drum to tilt and have spotty contact with
the brake shoe linings causing erratic action.
4. Front End Alignment—Misalignment of the front end,
particularly in regard to lim its on camber and
theoretical king pin inclination, will cause the brakes to
pull to one side.
HYDRO-BOOST
Prior to performing the Booster Function Tests, or the
A ccum ulator Leakdown Test, the following preliminary
checks must be made:
N O T IC E :
Power steering fluid and brake fluid cannot be
mixed. If brake seals contact steering fluid or steering
seals contact brake fluid, seal damage will result.
1. Check all power steering and brake lines and
connections for leaks and/or restrictions.
2. Check and fill brake master cylinder with BRAKE
FLUID.
3. Check and fill power steering pump reservoir with
POWER ST EER IN G FLUID. Be sure fluid is not
aerated (air mixed with fluid).
4. Check power steering pump belt for tension and/or
damage. Adjust if necessary.
5. Check engine idle speed and adjust if necessary.
6. Check steering pump pressure; Refer to Section 3B.
Summary of Contents for 1982 Light Duty Truck
Page 1: ......
Page 28: ...HEATER 1A 3 Fig lA 2 Heater Control C K Models Fig lA 3 Heater Control G Models...
Page 37: ...Fig 1A 11 T E E V A L V E A S M TEE AND VALVE C36...
Page 38: ...HEATER 1A 13 Fig 1A l2 Distributor Ducts G Models Fig 1A l5 Control Assembly G Models...
Page 39: ...1A 14 HEATER V IE W A V IE W B Fig 1A l7 Control Cable Routing G Models...
Page 42: ...HEATER 1A 19 Fig 1A 23 Auxiliary Heater Hose Routing...
Page 56: ...AIR CONDITIONING IB 13 Chart 1B 4 Pressure Cycling CCOT System Diagnosis...
Page 64: ...Fig 1B 17 C60 System Vacuum Diagram C K Series...
Page 65: ......
Page 66: ...Fig 1B 19 C60 Motor Home Chassis Wiring Diagram SWITCH AIR CONDITIONING IB 2 3...
Page 67: ...IB 24 AIR CONDITIONING Fig IB 20 1 P A C Harness Wiring...
Page 68: ...AIR CONDITIONING IB 25 VIE W A Fig IB 21 A C Compressor wiring...
Page 76: ...AIR CONDITIONING IB 33 Fig 1B 26 Compressor Mounting...
Page 91: ...IB 48 AIR CONDITIONING Fig 1B 59 C K Models Refrigerant Lines L6...
Page 150: ......
Page 162: ......
Page 164: ...2D 2 BODY Fig 2D 4 Typical Utility Vehicle Model...
Page 182: ...2D 20 BODY Fig 2D 51 Rear Door Controls Fig 2D 52 Rear Door Outside Handle and Lock Cylinder...
Page 193: ...BODY 2D 31 BELTS 3RD SEAT Fig 2D 82 Seat Belt Installation Suburban Driver Seat Suburban...
Page 194: ...2D 32 BODY Fig 2D 85 Passenger s Bucket Seat Chassis Cab...
Page 195: ...BODY 2D 33 Fig 2D 88 Rear Bench Seats Suburban...
Page 196: ...2D 34 BODY Fig 2D 89 CK Utility Seat Attachments...
Page 197: ...BODY 2D 35 Fig 2D 90 Seat Separator Compartment and Door CK Models...
Page 222: ......
Page 223: ...BODY 2D 61 Fig 2D 139 Front Seat Belt Installation...
Page 228: ......
Page 234: ......
Page 252: ...3B2 8 MANUAL STEERING GEAR Fig 3B2 11 Manual Steering Gear Exploded View...
Page 256: ......
Page 273: ...POWER STEERING SYSTEM 3B3 17 with LE3 Engine Exc HC4 LE4 LG9 LF4 LS9 LT9 and JB7 HC4 and JB8...
Page 342: ......
Page 389: ...REAR SUSPENSION 3D 7 Fig 3D 17 Rear Spring Installation C K Models...
Page 428: ...4 B 1 4 REAR AXLE Fig 4B 8 Gear Tooth Nomenclature Fig 4B 9 G ear Tooth Contact Pattern Check...
Page 444: ......
Page 454: ......
Page 468: ...4 B 5 2 REAR AXLE Fig 4B5 2 Rockwell Assembly...
Page 480: ...4 B 5 1 4 REAR AXLE...
Page 482: ...i...
Page 502: ......
Page 520: ......
Page 533: ...Fig 5 5 Front Brake Pipes and Hoses C K Models BRAKES 5 13...
Page 534: ...Fig 5 6 Front Brake Pipes and Hoses G M odels 5 14 B R A K E S...
Page 535: ...Fig 5 7 Front Brake Pipes and Hoses P Models BRAKES 5 15...
Page 536: ...5 16 BRAKES Fig 5 8 Rear Brake Hoses...
Page 538: ...5 18 BRAKES Fig 5 10 Parking Brake System Typical...
Page 539: ...BRAKES 5 19...
Page 570: ...5 50 BRAKES Fig 5 57 Power Steering Hose Routing C K Models...
Page 571: ...BRAKES 5 51 Fig 5 58 Power Steering Hose Routing G Models...
Page 572: ...Fig 5 59 Power Steering H ose Routing P Models 5 52 BRAKES...
Page 577: ...BRAKES 5 57 4 CONT A SECONDARY DIAPHRAGM B SECONDARY POWER 4 CONT C PRIMARY D Fig 5 5A Service...
Page 604: ......
Page 625: ...NOTES ENGINE 6 21...
Page 626: ......
Page 629: ...IN LINE 6 6A1 3 OIL PRESSURE SENDING UNIT Fig 6A1 1 In Line Engine Lubrication...
Page 630: ...6A1 4 IN LINE 6 Fig 6 A l 2 P Series Engine Front Mount...
Page 631: ...IN LINE 6 6A1 5 Fig 6Al 3 P Series Engine Rear Mount Fig 6 A l 4 C Series Engine Rear Mounts...
Page 634: ...6A1 8 IN LINE 6 Fig 6Al 7 K Series Engine Rear Mount...
Page 660: ......
Page 663: ...SMALL BLOCK 6A4 3 Fig 6A4 T Engine Lubrication...
Page 664: ...6A4 4 SMALL BLOCK Fig 6A4 2 Engine Lubrication...
Page 665: ...Fig 6A4 3 P Series Engine Mount Bracket...
Page 667: ...SMALL BLOCK 6A4 7 Fig 6A 4 5 P Series Engine Front Mount...
Page 668: ...6A4 8 SMALL BLOCK...
Page 669: ...SMALL BLOCK 6A4 9 Fig 6A 4 7 K Series Engine Mounts...
Page 670: ...6A4 10 SMALL BLOCK Fig 6A 4 8 C Series Engine Mounts...
Page 703: ...MARK IV 6A5 7 Fig 6A 5 6 P Series Engine Front Mount...
Page 704: ...6A5 8 MARK IV Fig 6 A 5 7 C Series Engine Mounts...
Page 731: ...6 2 DIESEL 6A7 3...
Page 760: ...6B 6 ENGINE COOLING Fig 6B 7 A C and A I R Adjustment...
Page 771: ...ENGINE COOLING 6B 17 Fig 6B 20 Engine O il C o o le r 6 2L Diesel...
Page 784: ......
Page 807: ...CARBURETOR MODEL 2SE 6C2 9 Fig 6C2 6 Typical 2SE Carburetor Assembly...
Page 820: ......
Page 830: ...6C4 10 CARBURETOR MODEL M4ME M4MC 101368 Fig 6C4 12 M 4M C M 4M E Carburetor Exploded View...
Page 848: ......
Page 876: ......
Page 888: ...6D 12 ENGINE ELECTRICAL Fig 6D 6C Generator Mounting Fig 6D 7C Generator Mounting...
Page 919: ...ENGINE ELECTRICAL 6D 43...
Page 934: ...Fig 6D 8E Starter M otor Mounting...
Page 974: ......
Page 1011: ...Figure 350C 25A Neutral Engine Running AUTOMATIC TRANSMISSION 350C 11...
Page 1054: ...Fig 7A 1C 400 Autom atic Transmission Side Cross Section Typical...
Page 1152: ...700 R4 40 AUTOMATIC TRANSMISSION Figure 700 R4 76 Transmission Assembly Exploded View...
Page 1162: ......
Page 1189: ...89MM MANUAL TRANSMISSION 7B3 5 Fig 7 3 4 4 Speed 89mm Exploded View...
Page 1219: ...CLUTCH 7C 5 Fig 7C 6 C K Truck Clutch Controls...
Page 1220: ...Fig 7C 7 G Truck Clutch Controls...
Page 1221: ...CLUTCH 7C 7 Fig 7C 8 P Truck Clutch Controls...
Page 1234: ...7E 2 TRANSFER CASE Fig 7E 1 Model 208 Transfer Case Cross Section...
Page 1252: ...7E 20 TRANSFER CASE Fig 7E 39 Transfer Case Attachment Typical...
Page 1278: ...8A 16 ELECTRICAL BODY AND CHASSIS Fig 8A 11 License Plate Lamps C K Series...
Page 1280: ...8A 18 ELECTRICAL BODY AND CHASSIS VIEW A VIEW B Fig 8A 15 CK Series Rear Lamp W iring...
Page 1281: ...ELECTRICAL BODY AND CHASSIS 8A 19 Fig 8A 16 CK Series Auxiliary W iring...
Page 1290: ...8B 8 ELECTRICAL AND WIRING Fig 8B 13 Seat Belt Reminder System Schematic...
Page 1292: ......
Page 1346: ...8C 54 INSTRUMENT PANEL AND GAGES Fig 8C 46 CK Series W iring 3 of 29...
Page 1351: ...INSTRUMENT PANEL AND GAGES 8C 59 SUBURBAN Fig 8C 51 CK Series W iring 8 of 29...
Page 1364: ...8C 72 INSTRUMENT PANEL AND GAGES Fig 8C 64 CK Series W iring 21 of 29...
Page 1365: ...INSTRUMENT PANEL AND GAGES 8C 73 CAB CRFW CAB CHASSIS Fig 8C 65 CK Series W iring 22 of 29...
Page 1366: ...8C 74 INSTRUMENT PANEL AND GAGES Fig 8C 66 CK Series W iring 23 of 29...
Page 1374: ...8C 82 INSTRUMENT PANEL AND GAGES Fig 8C 74 G Series W iring 2 of 19...
Page 1375: ...INSTRUMENT PANEL AND GAGES 8C 83 Fig 8C 75 G Series W iring 3 of 19...
Page 1376: ...8C 84 INSTRUMENT PANEL AND GAGES Fig 8C 76 G Series W iring 4 of 19...
Page 1379: ...INSTRUMENT PANEL AND GAGES 8C 87 Fig 8C 79 G Series W iring 7 of 19...
Page 1383: ...INSTRUMENT PANEL AND GAGES 8C 91 Fig 8C 83 G Series W iring 11 o f 19...
Page 1384: ...8C 92 INSTRUMENT PANEL AND GAGES BUS BARGWO Fig 8C 84 G Series W iring 12 of 19...
Page 1390: ...8C 98 INSTRUMENT PANEL AND GAGES Fig 8C 90 G Series W iring 18 of 19...
Page 1391: ...INSTRUMENT PANEL AND GAGES 8C 99 Fig 8C 91 G Series W iring 19 of 19...
Page 1392: ...8C 100 INSTRUMENT PANEL AND GAGES Fig 8C 92 P Series W iring 1 of 11...
Page 1393: ...INSTRUMENT PANEL AND GAGES 8C 101 Fig 8C 93 P Series W iring 2 of 11...
Page 1396: ...8C 104 INSTRUMENT PANEL AND GAGES Fig 8C 96 P Series W iring 5 of 11...
Page 1399: ...INSTRUMENT PANEL AND GAGES 8C 107 Fig 8C 99 P Series W iring 8 of 11...
Page 1401: ...INSTRUMENT PANEL AND GAGES 8C 109 START RUN OF LOCK ACC Fig 8C 101 P Series W iring 10 of 11...
Page 1415: ...ACCESSORIES 9 13 RADIO NOISE BLOWER MOTOR Fig 9 6R Radio Diagnosis Chart B...
Page 1416: ...9 14 ACCESSORIES D E A D R A D IO A M R A D IO I Fig 9 7R Radio Diagnosis Chart C...
Page 1417: ...ACCESSORIES 9 15 DEAD RADIO AM FM RADIO Fig 9 8R Radio Diagnosis Chart D...
Page 1435: ...t f l i t 1...