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Maintenance Information Buick Roadmaster VIII

Procedures 5 illustrations ~2081 words

VIN LOCATION

The Vehicle Identification Number (VIN) is located on the left side of the dash panel at the base of the windshield. The VIN chart explains the code characters.

VIN CODE ID EXPLANATION

Numbers preceding the explanations in the legend below refer to the sequence of characters as listed on VIN identification label. See VIN example below.

VIN Code ID Explanation. Scheme 8

Scheme 8: VIN Code ID Explanation
Scheme 8: VIN Code ID Explanation

SHORT TRIP/CITY & LONG TRIP/HIGHWAY SERVICE DEFINITIONS

Note. Starting in the 1996 model year, General Motors has renamed their maintenance schedules; One is referred to as the Short-Trip/City and the other is the Long Trip/Highway schedule. These schedule requirements are similar to the familiar Severe Service and Normal schedules and can be used in place of one another.

SEVERE & NORMAL SERVICE DEFINITIONS

Note. Use the Severe Service schedule if the vehicle to be serviced is operated under ANY (one or more) of these conditions

Service is recommended at mileage intervals based on vehicle operation. Service schedules are based on the following primary operating conditions

Severe Service

  1. Short Trips (4 Miles Or Less)
  2. When Most Trips Are Less Than 10 Miles And Outside Temperatures Remain Below Freezing.
  3. Towing Or Heavily Loaded
  4. Severe Dust Conditions
  5. Hot Weather, Stop-And-Go Driving
  6. Extensive Idling Conditions (Taxi Or Delivery Type Service)

Normal Service

  1. Driven More Than 10 Miles Daily
  2. No Severe Service Operating Conditions

Scheme 9

Scheme 9: SERVICE POINT LOCATIONS
Scheme 9: SERVICE POINT LOCATIONS

Scheme 10

Scheme 10
Scheme 10

Note. For more information regarding jacking or hoisting the vehicle, refer to the JACKING & HOISTING article in the WHEEL ALIGNMENT section.

SERVICE LABOR TIMES

Note. Labor times are provided, where available, within appropriate SERVICE INTERVAL table in SCHEDULED SERVICES article.

TIRE INFLATION

Tire pressure specification decal is attached to rear face of driver's door. Inflation pressures listed on decal are always cold pressures and must never exceed maximum values molded into tire side wall. These pressures should be used for all driving conditions, as they provide the best balance of fuel economy, tire life, riding comfort and handling.

Note. When using compact spare tire, it must be inflated to 60 psi, and vehicle must not be driven faster than 50 MPH.

WHEEL TORQUE SPECIFICATIONS

ApplicationFt. Lbs. (N.m)
Sedan
1/2 x 20"100 (140)
7/16" x 20"80 (110)
Station Wagon100 (140)
(1) Always tighten wheel lug nuts in a crisscross pattern. All wheel lug nuts have right-hand threads.
(1)Always tighten wheel lug nuts in a crisscross pattern. All wheel lug nuts have right-hand threads.

TORQUE SPECIFICATIONS (1)

BATTERY SPECIFICATIONS

CAUTIONWhen battery is disconnected, vehicles equipped with computers may lose memory data. When battery power is restored, driveability problems may exist on some vehicles. These vehicles may require a relearn procedure. See COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION section.

SUPPLEMENTAL RESTRAINT SYSTEM (AIR BAG)

Note. See the AIR BAGS article in the ACCESSORIES/SAFETY EQUIPMENT Section.

Modifications or improper maintenance, including incorrect removal and installation of the Supplemental Restraint System (SRS), can adversely affect system performance. DO NOT cover, obstruct or change the steering wheel horn pad in any way, as such action could cause improper function of the system. Use only plain water when cleaning the horn pad. Solvents or cleaners could adversely affect the air bag cover and cause improper deployment of the system.

WARNINGTo avoid injury from accidental air bag deployment, read and carefully follow all warnings and service precautions. See appropriate AIR BAGS article in ACCESSORIES/SAFETY EQUIPMENT.

Modification to the air bag system component or wiring can adversely affect system performance and possibly cause injury.

CAUTIONThe Diagnostic Energy Reserve Module (DERM) can maintain enough voltage to cause a deployment of the inflator module for up to 10 minutes after the ignition switch is turned off and the battery is disconnected. Many of the service procedures require disconnection of the inflator module to avoid an accidental deployment.
CAUTIONDisconnect negative battery cable before servicing any air bag system, steering column or passenger side dash component. After any repair, turn ignition key to the ON position from passenger's side of vehicle in case of accidental air bag inflation

AIR CONDITIONING SERVICING

CAUTIONAvoid breathing R-134a refrigerant and PAG lubricant vapors, exposure may irritate eyes, nose and throat. To remove R-134a from system use R-134a recycling equipment that meets SAE J2210 specifications. If accidental system discharge occurs, ventilate work area before resuming service.
WARNINGR-134a service equipment or vehicle A/C systems SHOULD NOT be pressure tested or leak tested with compressed air. Some mixtures of air/R134a have shown to be combustible at elevated pressures. These mixtures are dangerous and may cause fire and/or explosions. See AIR CONDITIONING SERVICE article in GENERAL INFORMATION section.

ANTI-LOCK BRAKE SYSTEM

The anti-lock brake system contains electronic equipment that can be susceptible to interference caused by improperly installed or high output radio transmitting equipment. Since this interference could cause the possible loss of the anti-lock braking capability, such equipment should be installed by qualified professionals.

On models equipped with anti-lock brake systems, ALWAYS observe the following cautions

  1. DO NOT attempt to bleed hydraulic system without first referring to the appropriate ANTI-LOCK BRAKE SYSTEM article in the BRAKES Section.
  2. DO NOT mix tire sizes. As long as tires remain close to the original diameter, increasing the width is acceptable. Rolling diameter must be identical for all 4 tires. Some manufacturers recommend tires of the same brand, style and type. Failure to follow this precaution may cause inaccurate wheel speed readings.
  3. Use ONLY recommended brake fluids. DO NOT use silicone brake fluids in an ABS-equipped vehicle.

REPLACING BLOWN FUSES

Before replacing a blown fuse, remove ignition key, turn off all lights and accessories to avoid damaging the electrical system. Be sure to use fuse with the correct indicated amperage rating. The use of an incorrect amperage rating fuse may result in a dangerous electrical system overload.

BATTERY

DO NOT test battery if it shows any signs of freezing, leaking, loose posts or low electrolyte level; an explosive condition could result.

BATTERY WARNING

WARNINGWhen battery is disconnected, vehicles equipped with computers may lose memory data. When battery power is restored, driveability problems may exist on some vehicles. These vehicles may require a relearn procedure. See the COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION section.

BRAKE PAD WEAR INDICATOR

Indicator will cause a squealing or scraping noise, warning that brake pads need replacement.

CATALYTIC CONVERTER

To prevent catalytic converter overheating, DO NOT allow engine to idle for more than 20 minutes.

COOLANT (DEX-COOL 1995-96 MODELS)

CAUTIONSome 1995 build-out and all 1996 models have DEX-COOL engine coolant installed at the factory. DEX-COOL coolant is a silicate-free coolant that is orange in color. It should not be mixed with regular ethylene-glycol coolant. To avoid possible damage to vehicle cooling system, visually check engine coolant color before adding and/or changing engine coolant. Vehicle should have an identification label placed under the hood stating what type coolant is installed.

COOLANT (PROPYLENE-GLYCOL FORMULATIONS)

CAUTIONTo avoid possible damage to vehicle use only ethylene-glycol based coolants with a mixture ratio from 44-68% anti-freeze. DO NOT use 100% anti-freeze as it will cause the formation of cooling system deposits. This results in coolant temperatures of over 300° F (149°C) which can melt plastics. 100% anti-freeze has a freeze point of only -8° F (-22°C).
CAUTIONPropylene-Glycol Mixtures has a smaller temperature range than Ethylene-Glycol. The temperature range (freeze-boil) of a 50/50 Anti-Freeze/Water Mix is as follows: Propylene-Glycol -26° F (-32°C) - 257° F (125°C); Ethylene-Glycol -35° F (-37°C) - 263° F (128°C).
CAUTIONPropylene-Glycol/Ethylene-Glycol Mixtures can cause the destabilization of various corrosion inhibitors. Also Propylene-Glycol/Ethylene-Glycol has a different specific gravity than Ethylene-Glycol coolant, which will result in inaccurate freeze point calculations.

ELECTROSTATIC DISCHARGE SENSITIVE (ESD) PARTS

WARNINGMany solid state electrical components can be damaged by static electricity (ESD). Some will display a warning label, but many will not. Discharge personal static electricity by touching a metal ground point on the vehicle prior to servicing any ESD sensitive component.

FUEL SYSTEM SERVICE

WARNINGRelieve fuel system pressure prior to servicing any fuel system component.

HALOGEN BULBS

WARNINGHalogen bulbs contain pressurized gas which may explode if overheated. DO NOT touch glass portion of bulb with bare hands. Eye protection should be worn when handling or working around halogen bulbs.

METHANOL GASOLINE

CAUTIONFuel that is more than 5% methanol should not be used in this vehicle. It can corrode metal parts in the fuel system, and damage plastic and rubber parts. Even at 5% methanol or less, solvents and corrosion preventers must be used with this fuel to avoid these problems.

RADIATOR CAP

CAUTIONAlways disconnect the fan motor when working near the radiator fan. The fan is temperature controlled and could start at any time even when the ignition key is in the OFF position. DO NOT loosen or remove radiator cap when cooling system is hot.

RADIATOR FAN

WARNINGKeep hands away from radiator fan. Fan is controlled by a thermostatic switch which may come on or run for up to 15 minutes even after engine is turned off.

RADIATOR FAN WITH TOW PACKAGE

WARNINGKeep hands away from mechanical (fan-clutch) radiator fan.

SPARK PLUGS

Note. Allow engine to cool before removing spark plugs from aluminum cylinder heads.

TAILGATE

WARNINGDO NOT drive vehicle with tailgate open, as carbon monoxide can enter vehicle.

TRACTION CONTROL SYSTEM (IF EQUIPPED)

CAUTIONIf tires are allowed to spin at high speeds when TRACTION OFF light is on, tires can explode. Also, spinning the tires with the warning light on can cause the transaxle to overheat. DO NOT spin wheels above 35 MPH.

WARRANTY INFORMATION

CAUTIONDue to the different warranties offered in various regions and the variety of after-market extended warranties available, please refer to the warranty package that came with the vehicle to verify all warranty options.

BUMPER TO BUMPER PLUS COVERAGE LIMITED WARRANTY (1991-93)

Everything covered for 3 years or 50,000 miles, whichever occurs first. Covered by this warranty are any repairs to vehicle which have proven defective during material and workmanship in normal use (tires excluded). Warranty repairs (parts and labor) will be made by the Dealer at no charge using new or remanufactured parts by the Dealer. This warranty is subject to a 100 deductible for each repair visit after the first year or 12,000 miles, whichever occurs first. Maintenance items are covered up to their first scheduled replacement interval only.

Note. 1992-93 vehicles are covered for 3 years or 36,000 miles with no deductible.

CORROSION WARRANTY

Warranty covers any rust-through in body sheet metal due to corrosion. Warranty period is 6 years or 100,000 miles, whichever occurs first. Warranty begins on date vehicle is delivered or put in use, whichever occurs first.

EMISSION COMPONENTS "DEFECT" WARRANTY

General Motors Corporation warrants all GM's emission components in vehicle to be free of defects in material and workmanship, which would cause it to fail to meet Federal standards for emission control system at the time vehicle was built. Warranty begins on date vehicle is delivered or first put in use, whichever occurs first. Refer to customer's copy of warranty information for exact warranty periods on specific models.

EMISSION "PERFORMANCE" WARRANTY

The following are primary components affecting vehicle's emissions performance. Other emission control-related parts are covered by the Performance warranty, where applicable. If another part fails due to the failure of one of these components, both parts are covered.

Primary components are normally covered for 5 years or 50,000 miles with a few exceptions. Refer to customers copy of warranty information for exact warranty periods on specific models.

Gasoline Engines

  1. Air Injector Reactor (AIR) Pump, Air Distributor And Valves
  2. Pulse AIR Valve And Associated Parts
  3. PCV Valve System And Oil Filler Cap
  4. EGR Valve And Associated Controls
  5. Choke Switches And Carburetor Parts
  6. Engine Control Module And Associated Sensors (If Equipped)
  7. Electronic Fuel Injection System
  8. Carburetor Feedback Control System
  9. Throttle Return Control Parts (If Equipped)
  10. Catalytic Converter, Catalyst And Associated Parts
  11. Fuel Tank, Filler Cap, Restrictor And Vapor Control Valves
  12. Evaporative Emission Control Carbon Canister And Associated Controls
  13. Emission Related Hoses, Clamps, Belts, Pulley, Tubes, Fittings And Wiring Harness
  14. Thermostatic Air Cleaner Switch, Control Valve And Associated Parts
  15. EFE Valve, Heater And Associated Controls (If Equipped)
  16. Exhaust System-To-Catalytic Converter
  17. Distributor Parts And Associated Controls
  18. Spark Plugs And Ignition Wires
  19. Intake, Exhaust Manifolds And Turbocharger (California)

FUSIBLE LINKS

Fusible links will melt to prevent fire if a large current flows through electrical systems without passing through fuses.

Scheme 11

Scheme 11: FUSE PANEL IDENTIFICATION (1991-93 ROADMASTER)
Scheme 11: FUSE PANEL IDENTIFICATION (1991-93 ROADMASTER)
WARNINGAlways disconnect battery ground cable before servicing "high-current fuses. It is recommended that "high-current" fuses be replaced by a qualified technician.

Fuse & Circuit Breaker Identification

  1. 1 - 15 Amp Lighted Mirror, Underhood Light, Interior Courtesy Lights, Power Antenna Relay, Power Door Locks, Power Mirrors, Vanity Mirrors, Reading Lights (Estate Wagon), Keyless Entry Module Estate Wagon), Rear Glass Release Relay (Estate Wagon), Tailgate Lock Switch (Estate Wagon)
  2. 2 - 15 Amp Audio Alarm Module, Cigarette Lighter, Instrument Panel Compartment Light, Luggage Compartment Light (Sedan), Radio Memory, Low Oil Module, Trunk Lid Release Relay (Sedan), Rear Wiper Motor (Estate Wagon)
  3. 3 - 10 Amp Electronic Air Conditioning, Rear Defogger Relay (1993)
  4. 4 - 25 Amp Electronic Level Control
  5. 5 - 7.5 Amp Interior Lights Dimming
  6. 6 - 20 Amp Alternator, Heater-A/C Controls, Electronic A/C Control Head Estate Wagon), Daytime Running Lights, EVO Controller Sedan), A/C Control Relay (Sedan), Solenoid Assembly & Control Relay (Estate Wagon), Keyless Entry Module (Estate Wagon)
  7. 7 - 30 Amp Electronic A/C Power Module
  8. 8 - 25 Amp (Exc. 1993 Wagon) 15 Amp (1993 Wagon) Trunk Lid Pull-Down Unit (Sedan), Horn Relay, Rear Window Wiper/Washer Switch (Estate Wagon)
  9. 9 - 10 Amp Radio
  10. 10 - 25 Amp Windshield Wiper/Washer, Washer Fluid Level Switch
  11. 11 - 7.5 Amp Fuel Injectors
  12. 12 - 10 Amp Arming Sensor, Diagnostic Energy Reserve Module (DERM)
  13. 13 - 10 Amp Electronic Control Module, Electronic Spark Control Module, Emission Control Solenoids, Instrument Cluster, Vehicle Speed Sensor Module
  14. 14 - 15 Amp Taillights, Parking & Side Marker Lights, Interior Lights
  15. 15 - 30 Amp Rear Defogger
  16. 16 - 7.5 Amp Heated Mirrors
  17. 17 - 15 Amp Audio Alarm Module, Defogger Relay/Timer, Diagnostic Energy Reserve Module (DERM), Electronic Compass, Fluid Warning Center, Headlight Switch Illumination Light, Electronic Level Control (ELC) Height, Sensor (Estate Wagon), Overvoltage Protection Relay (Estate Wagon), Cruise Release Switch Estate Wagon), Instrument Cluster, Low Coolant Module, Twilight Sentinel, Daytime Running Lights Module, TCC Brake Switch, Keyless Entry Module (Sedan), Fluid Warning Center Estate Wagon), Low Coolant Module (Estate Wagon)
  18. 18 - 15 Amp Back-Up Lights, Turn Flasher, Turn Lights, Trunk Lid Release Relay (Sedan), ELC Height Sensor (Sedan), Cruise Control Estate Wagon)
  19. 19 - 20 Amp Brake Lights, Hazard Flasher
  20. 20 - 5 Amp Diagnostic Energy Reserve Module (DERM), Electronic Control Module
  21. 21 - Circuit Breaker Power Seat Switches, Power Door Lock Relay, Lumbar Switches Sedan), Recliner Switches, Keyless Entry, Tailgate Lock Relay (Estate Wagon)
  22. 22 - Circuit Breaker Power Window Switches

Scheme 12

Scheme 12: FUSE PANEL IDENTIFICATION (1994-96 ROADMASTER)
Scheme 12: FUSE PANEL IDENTIFICATION (1994-96 ROADMASTER)
  1. 1 - Blank
  2. 2 - Blank
  3. 3 - Blank
  4. 4 - Blank
  5. 5 - Blank
  6. 6 - 15 Amp Turn Signal Lamp Flasher, Park Neutral Position Sw.
  7. 7 - 10 Amp Electronic Brake Control Module
  8. 8 - 15 Amp Wagon Rear Wiper
  9. 9 - 10 Amp Radio
  10. 10 - 25 Amp Windshield Wiper/Washer Switch
  11. 11 - 10 Amp Rear Defog Relay, SDM, Rear Compartment Lid Release Sw. Headlamp Sw., I/P Cluster, Rear Defog Sw.
  12. 12 - 10 Amp Auto Level Control Sensor, Ignition Sw.
  13. 13 - 10 Amp Inside Rearview Mirror, Warning Alarm, Cruise Control Release Sw., Headlamp Auto Control Module, Daytime Running Lamp Control Module, Remote Control Door Lock Receiver
  14. 14 - 10 Amp Theft Deterrent Module
  15. 15 - 15 Amp Inflatable Restraint Diagnostic Energy Reserve Module
  16. 16 - 10 Amp Cruise Control Module, Cruise Control Sw.
  17. 17 - 20 Amp Heater & A/C Control, Low Blower Motor Relay
  18. 18 - 20 Amp Power Steering Control Module
  19. 19 - Blank
  20. 20 - 10 Amp Electric Actuator, Vacuum Electric Solenoid, Heater & A/C Control, Instrument Cluster
  21. 21 - Blank
  22. 22 - Blank
  23. 23 - Blank
  24. 24 - 10 Amp SDM, Theft Deterrent Relay
  25. 25 - Blank
  26. 26 - 20 Amp Radio Power Antenna Relay
  27. 27 - 10 Amp Auto Level Control Sensor, Rear Compartment Courtesy Lamp, Mercury Switch
  28. 28 - 20 Amp Cigar Lighter
  29. 29 - 20 Amp Remote Control Door Lock Receiver, Liftgate Wiper Latch Sw., Rear Glass Release Sw., Rear Compartment Lid Release Sw.
  30. 30 - 15 Amp Radio
  31. 31 - 20 Amp Headlamp Switch, Headlamp Auto Control, Daytime Running Lamps Control Module
  32. 32 - 25 Amp Horn Relay
  33. 33 - 10 Amp Warning Alarm, I/P Compartment Lamp Sw., I/P Cluster, Heater and A/C
  34. 34 - 10 Amp Theft Deterrent Module
  35. 35 - 15 Amp Courtesy Lamp Relay, Front Doors Lock Sw., Door Courtesy Lamps, Outside Remote Control Mirror, Inside Rearview Mirror, Visor Vanity Mirror
  36. 36 - 15 Amp Rear Window Wiper, Deck Lid Pull Down Actuator
  37. 37 - 20 Amp Stoplamp Sw., Hazard Lamp Flasher
  38. 38 - Blank
  39. 39 - Blank
  40. 40 - 30 Amp Blower Motor Control Module
  41. 41 - 10 Amp Turn Signal Sw., Side Marker Lamp, Turn Park Lamp
  42. 42 - 10 Amp Heater & A/C Control, Headlamp Sw., Instrument Cluster, Radio, Headlamp & Instrument Panel Lamp Dimmer Sw., Panel Lamps Dimming Module, Interior Lights
  43. 43 - 10 Amp Opera Lamps, License Lamp, Marker Lamps, Taillamps, Tail/Turn Stoplamps
  44. 44 - 10 Amp Heater Power Mirrors
  45. 45 - Blank
  46. 46 - Blank
  47. 47 - 30 Amp (Circuit Breaker) Master Power Window Sw., Power Window Lockout Sw., Power Window Control Module
  48. 48 - 30 Amp (Circuit Breaker) Door Lock Relay, Power Seat Sw., Recline Sw., Passenger Seat Lumbar Control
  49. 49 - 30 Amp (Circuit Breaker) Rear Window Defog Sw., Rear Window Defog Relay
  50. 50 - Blank

See also:
• JACKING & HOISTING

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