INTRODUCTION
Use this article to quickly find specifications related to servicing and on-vehicle adjustments. This article may be used for quick reference when you are familiar with proper adjustment procedures and only need a specification.
MODEL IDENTIFICATION
Vehicle model is identified by fifth character of Vehicle Identification Number (VIN). VIN is stamped on metal pad on top of left end of instrument panel, near windshield. See MODEL IDENTIFICATION table.
| Series (1) | Model |
|---|
| "C" | 2WD Pickup, Suburban, Tahoe & Yukon |
| "K" | 4WD Pickup, Suburban, Tahoe & Yukon |
| (1) Vehicle series is fifth character of VIN. |
| (1) | Vehicle series is fifth character of VIN. |
CAPACITIES
| Application | Cold Crank Amps @ 0°F (-18°C) | Reserve Capacity Minutes |
|---|
| 4.3L (VIN W) | 600 | 130 |
| 5.0L (VIN M) | 600 | 130 |
| 5.7L (VIN R) | 600 | 130 |
| 6.5L (VIN F, P & S) (1) | 600 | 130 |
| 7.4L (VIN J) | 600 | 130 |
| (1) 2 batteries per vehicle. |
| (1) | 2 batteries per vehicle. |
| Application | (1) Quantity: Qts. (L) |
|---|
| Crankcase |
| 4.3L (VIN W) | (2) 4.5 (4.3) |
| 5.0L (VIN M) | (2) 5.0 (4.8) |
| 5.7L (VIN R) | (2) 5.0 (4.8) |
| 6.5L (VIN F, P & S) | (3) 7.0 (6.5) |
| 7.4L (VIN J) | (2) 7.0 (6.5) |
| Cooling System (Includes Heater) (4) |
| 4.3L (VIN W) | 12.7 (12.3) |
| 5.0L (VIN M) |
| With A/C | 18.0 (17.0) |
| Without A/C | 17.5 (16.6) |
| 5.7L (VIN R) |
| Standard |
| With A/C | 20 (19) |
| Without A/C | 17.5 (16.6) |
| Heavy Duty |
| With A/C | 27.0 (25.5) |
| Without A/C | 26.4 (25.0) |
| 6.5L (VIN F, P & S) | 27.5 (26.0) |
| 7.4L (VIN J) |
| Standard |
| With A/C | 27.5 (26) |
| Without A/C | 25 (23.5) |
| Heavy Duty |
| With A/C | 28.5 (27) |
| Without A/C | 26.4 (25.0) |
| Automatic Transmission (Dexron-II) (5) |
| 4.3L (VIN W) | 5.0 (4.7) |
| Except 4.3L |
| With 4L 60-5 | 5.0 (4.7) |
| With 4L 80-E | 7.7 (7.3) |
| Manual Transmission |
| 4.3L (VIN W) | (6) 2.1 (2.0) |
| Except 4.3L |
| 4-Speed | (7) 4.0 (3.8) |
| 5-Speed | (8) 2.1 (2.0) |
| (1) Fluid capacities listed are approximate. Always fill to FULL mark. (2) Includes oil filter capacity. (3) Use of synthetic 10W-30 motor oil is required on Turbo models. (4) Add 3 qts. (2.8L) coolant for models equipped with rear heater. (5) Drain and refill capacity only. Does not include torque converter. (6) Synchromesh Transmission Fluid (9985648-T2732). (7) Castrol Syntorq LT transmission fluid. (8) Synchromesh Transmission Fluid (9985648-T2850). |
| (1) | Fluid capacities listed are approximate. Always fill to FULL mark. |
| (2) | Includes oil filter capacity. |
| (3) | Use of synthetic 10W-30 motor oil is required on Turbo models. |
| (4) | Add 3 qts. (2.8L) coolant for models equipped with rear heater. |
| (5) | Drain and refill capacity only. Does not include torque converter. |
| (6) | Synchromesh Transmission Fluid (9985648-T2732). |
| (7) | Castrol Syntorq LT transmission fluid. |
| (8) | Synchromesh Transmission Fluid (9985648-T2850). |
SERVICE INTERVALS & SPECIFICATIONS
| Component | Interval (Miles) |
|---|
| Air Filter | 30,000 |
| Coolant | 30,000 |
| Fuel Filter | (1) 60,000 |
| Oil & Filter | (2) (3) 7500 |
| Spark Plugs | 30,000 |
| (1) On diesel engines, replace every 30,000 miles. (2) On diesel engines, replace every 5000 miles. (3) On turbo models, replace every 3000 miles. |
| (1) | On diesel engines, replace every 30,000 miles. |
| (2) | On diesel engines, replace every 5000 miles. |
| (3) | On turbo models, replace every 3000 miles. |
BELT TENSION
| Application | (1) Tension: Lbs. (kg) |
|---|
| All Models | (1) |
| (1) Serpentine belt tension is maintained automatically by a spring-tensioned idler pulley. No adjustment is necessary. |
| (1) | Serpentine belt tension is maintained automatically by a spring-tensioned idler pulley. No adjustment is necessary. |
ENGINE COMPRESSION
| Application | Compression Ratio |
|---|
| 4.3L (VIN W) | 9.2:1 |
| 5.0L (VIN M) | 9.4:1 |
| 5.7L (VIN R) | 9.4:1 |
| 6.5L Diesel Turbo Diesel (VIN F, P & S) | 21.5:1 |
| 7.4L (VIN J) | 9.0:1 |
VALVE CLEARANCE
Note. All models are equipped with hydraulic lifters. No adjustments are required.
IGNITION COIL
| Application | Ohms |
|---|
| All Models | 500-1500 |
HIGH TENSION WIRE RESISTANCE
| Application | Ohms |
|---|
| All Models | 30,000 Maximum |
HIGH TENSION WIRE RESISTANCE
SPARK PLUGS
| Application | AC |
|---|
| 4.3L (VIN W) | 41-932 |
| 5.0L (VIN M), 5.7L (VIN R) & 7.4L (VIN J) | 41-932 |
| (1) Platinum tip, 100,000 mile spark plug. |
| (1) | Platinum tip, 100,000 mile spark plug. |
| Application | Gap: In. (mm) | Torque: Ft. Lbs. (N.m) |
|---|
| 4.3L (VIN W) | .060 (1.52) | 15 (20) |
| 5.0L (VIN M) | .060 (1.52) | 15 (20) |
| 5.7L (VIN R) | .060 (1.52) | 15 (20) |
| 7.4L (VIN J) | .060 (1.52) | 15 (20) |
SPARK PLUG SPECIFICATIONS
FIRING ORDER & TIMING MARKS
Firing Order & Timing Marks (4.3L). Scheme 1
Scheme 1: Firing Order & Timing Marks (4.3L)
Firing Order & Timing Marks (5.0L, 5.7L & 7.4L - With Old Style Distributor Cap). Scheme 2
Scheme 2: Firing Order & Timing Marks (5.0L, 5.7L & 7.4L - With Old Style Distributor Cap)
Firing Order & Timing Marks (5.0L, 5.7L & 7.4L - With New Style Distributor Cap). Scheme 3
Scheme 3: Firing Order & Timing Marks (5.0L, 5.7L & 7.4L - With New Style Distributor Cap)
Firing Order (6.5L Diesel). Scheme 4
Scheme 4: Firing Order (6.5L Diesel)
IGNITION TIMING
Note. For timing adjustment procedures, see ADJUSTMENTS article.
| Application | (1) Man. Trans. | (2) Auto. Trans. |
|---|
| 4.3L (VIN W) | (3) | (3) |
| 5.0L (VIN M) | 0 @ Idle | 0 @ Idle |
| 5.7L (VIN R) | 0 @ Idle | 0 @ Idle |
| 7.4L (VIN J) | 0 @ Idle | 0 @ Idle |
| (1) With transmission in Neutral. (2) With transmission in Neutral or Park. (3) Timing is not adjustable. |
| (1) | With transmission in Neutral. |
| (2) | With transmission in Neutral or Park. |
| (3) | Timing is not adjustable. |
IGNITION TIMING (Degrees BTDC @ RPM)
FUEL PUMP
| Application | Psi (kg/cm 2 ) |
|---|
| 4.3L (VIN W) | 60-66 (4.2-4.6) |
| 5.0L (VIN M) & 5.7L (VIN R) | 60-66 (4.2-4.6) |
| 6.5L Diesel (VIN F, P & S) | 5.0-8.0 (0.35-0.56) |
| 7.4L (VIN J) | 56-63 (4.0-4.4) |
INJECTOR RESISTANCE
| Application | Ohms |
|---|
| All | 11.8-12.6 |
| (1) Injector resistance specification is at 140°F (60°C). |
| (1) | Injector resistance specification is at 140°F (60°C). |
INJECTOR RESISTANCE SPECIFICATIONS (1)
IDLE SPEED & MIXTURE
Note. Idle mixture on fuel injected models is controlled by Electronic Control Module (ECM) and is not adjustable. Controlled idle speed and IAC count can be checked using scan tester. See CONTROLLED IDLE SPEED & IAC COUNT table.
| Application | Idle RPM | (1) IAC Counts |
|---|
| 4.3L CSI |
| Auto. Trans. (2) (3) | 537 | 5-30 |
| Auto. Trans. (2) (3) | 650 | 5-30 |
| Man. Trans. (4) | 550 | 5-30 |
| 5.0L CSI |
| Auto. Trans. (2) | 500 | 5-30 |
| Man. Trans. (4) | 600 | 5-30 |
| 5.7L CSI |
| Under 8500 GVW |
| Auto. Trans. (2) | 550 | 5-30 |
| Man. Trans. (4) | 700 | 5-30 |
| Over 8500 GVW |
| Auto. Trans. (2) | 550 | 5-30 |
| Man. Trans. (4) | 600 | 5-30 |
| 7.4L CSI |
| Auto. Trans. (2) | 675 | 5-30 |
| Man. Trans. (4) | 700 | 5-30 |
| (1) Add 2 counts for engines with less than 500 miles. On 4.3L and V8 engines, add 2 counts for every 1000 ft. above sea level. (2) Automatic transmission in Drive. (3) Calibration identification is not available. IAC count and actual RPM should correspond to one of these calibrations. (4) Manual transmission in Neutral. Tech 1 scan tester will display "RDL" with transmission in Neutral. |
| (1) | Add 2 counts for engines with less than 500 miles. On 4.3L and V8 engines, add 2 counts for every 1000 ft. above sea level. |
| (2) | Automatic transmission in Drive. |
| (3) | Calibration identification is not available. IAC count and actual RPM should correspond to one of these calibrations. |
| (4) | Manual transmission in Neutral. Tech 1 scan tester will display "RDL" with transmission in Neutral. |
CONTROLLED IDLE SPEED & IAC COUNT
MINIMUM IDLE SPEED
Note. Minimum idle speed adjustment can only be performed on 7.4L engines. For minimum idle speed adjustment procedures, see ADJUSTMENTS article.
| Application | RPM |
|---|
| 7.4L (VIN J) |
| Auto. Trans. (2) | 600-650 |
| Man. Trans. (3) | 675-725 |
| (1) Idle speed with seated IAC is lower than specified if engine has less than 500 miles or when checked at altitudes above 1500 feet. (2) Automatic transmission in Drive. (3) Manual transmission in Neutral. |
| (1) | Idle speed with seated IAC is lower than specified if engine has less than 500 miles or when checked at altitudes above 1500 feet. |
| (2) | Automatic transmission in Drive. |
| (3) | Manual transmission in Neutral. |
THROTTLE POSITION (TP) SENSOR (6.5L DIESEL)
Note. TP sensor has been replaced by a non-adjustable Accelerator Pedal Position (APP) module. APP signals PCM which signals fuel solenoid driver and fuel injector control. Throttle control is electronic with NO mechanical link from engine to pedal.
