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HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 683 (ENGINE MECHANICAL - 3.1L)SPECIFICATIONSENGINE MECHANICAL SPECIFICATIONS
1999 GMC Forward Control 5.7 R, Automatic

Engine Mechanical Specifications

1999 GMC Forward Control 5.7 R, AutomaticSECTION Engine Mechanical Specifications
WARNING: This page is about a different car, the 2003 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
ENGINE MECHANICAL SPECIFICATIONS

Application Specification
Metric English
General Data
  Engine Type 60° V-6
  Displacement 3.1L 191 cu in
  RPO LG8
  VIN J
  Bore 89 mm 3.50 in
  Stroke 84 mm 3.31 in
  Compression Ratio 9.6:1
  Firing Order 1-2-3-4-5-6
  Spark Plug Gap 1.52 mm 0.60 in
Block
  Camshaft Bearing Bore Diameter - ID 47.516-47.541 mm 1.871-1.872 in
  Camshaft Bearing Bore Diameter - Front and Rear 51.03-51.08 mm 2.009-2.011 in
  Camshaft Bearing Bore Diameter - Middle #2, #3 50.77-50.82 mm 1.999-2.001 in
  Crankshaft Main Bearing Bore Diameter 72.1535-72.1695 mm 2.8407-2.8413 in
  Crankshaft Main Bearing Bore Out-of-Round 0.008 mm 0.0003 in
  Cylinder Bore Diameter - Production 89.016-89.034 mm 3.5046-3.5053 in
  Cylinder Bore Diameter - Service 89.016-89.042 mm 3.5046-3.5056 in
  Cylinder Bore Out-of-Round - Diametral - Production 0.020 mm 0.0008 in
  Cylinder Bore Out-of-Round - Diametral - Service 0.025 mm 0.001 in
  Cylinder Bore Taper - Production 0.020 mm 0.0008 in
  Cylinder Bore Taper - Service 0.025 mm 0.001 in
  Cylinder Head Deck Height 224 mm 8.819 in
  Cylinder Head Deck Surface Flatness 0.05 mm per 152 mm 0.002 in per 6 in
  Valve Lifter Bore Diameter 21.417-21.455 mm 0.843-0.845 in
Camshaft
  Camshaft Bearing Inside Diameter 47.516-47.541 mm 1.871-1.872 in
  Camshaft Journal Diameter 47.443-47.468 mm 1.868-1.869 in
  Camshaft Journal Out-of-Round 0.003 mm 0.00012 in
  Camshaft Journal to Bearing Clearance 0.048-0.098 mm 0.002-0.004 in
  Camshaft Lobe Lift - Exhaust 6.9263 mm 0.2727 in
  Camshaft Lobe Lift - Intake 6.9263 mm 0.2727 in
  Camshaft Runout 0.050 mm 0.002 in
Cooling System
  Capacity Engine RPM 12.4 liters 13.1 quarts
  Thermostat Full Open Temperature 195 degrees
Connecting Rod
  Connecting Rod Bearing Clearance 0.18-0.062 mm 0.0007-0.017 in
  Connecting Rod Bore Diameter 53.962-53.978 mm 2.124-2.125 in
  Connecting Rod Bore Out-of-Round 0.008 mm 0.00031 in
  Connecting Rod Length - Center to Center 144.75-144.81 mm 5.69-5.70 in
  Connecting Rod Side Clearance 0.25-0.37 mm 0.010-0.015 in
Crankshaft
  Connecting Rod Journal Diameter 50.768-50.784 mm 1.9987-1.9994 in
  Connecting Rod Journal Out-of-Round 0.005 mm 0.0002 in
  Connecting Rod Journal Taper 0.005 mm 0.0002 in
  Connecting Rod Journal Width 21.92-22.08 mm 8.62-8.69 in
  Crankshaft End Play 0.060-0.210 mm 0.0024-0.0083 in
  Crankshaft Main Bearing Journal Width - #1 29.5 mm 1.161 in
  Crankshaft Main Bearing Journal Width - #2 24.0 mm 0.945 in
  Crankshaft Main Bearing Journal Width - #3 24.04 mm 0.946 in
  Crankshaft Main Bearing Journal Width - #4 35.8 mm 1.409 in
  Crankshaft Main Bearing Clearance - Except #3 0.019-0.064 mm 0.0008-0.0025 in
  Crankshaft Main Bearing Clearance - #3 Thrust Bearing 0.032-0.077 mm 0.0012-0.0030 in
  Crankshaft Main Journal Diameter 67.239-67.257 mm 2.6473-2.6483 in
  Crankshaft Main Journal Out-of-Round 0.005 mm 0.0002 in
  Crankshaft Main Journal Taper 0.005 mm 0.0002 in
  Crankshaft Rear Flange Runout 0.04 mm 0.0016 in
  Crankshaft Reluctor Ring Runout - Max 0.34 mm 0.0134 in
  Crankshaft Runout 0.025 mm 0.0010 in
Cylinder Head
  Combustion Chamber Depth - at Measurement Point 2.2 mm 0.087 in
  Surface Finish - Maximum 2.8 RA
  Surface Flatness - Block Deck 0.08 mm per 152 mm 0.003 in per 6 in
  Surface Flatness - Exhaust Manifold Deck 0.1 mm 0.004 in
  Surface Flatness - Intake Manifold Deck 0.1 mm 0.004 in
  Valve Guide Bore - Exhaust 8.01 mm 0.315 in
  Valve Guide Bore - Intake 8.01 mm 0.315 in
  Valve Guide Installed Height 16.6 mm 0.654 in
Lubrication System
  Oil Capacity - with Filter 4.3 liters 4.5 quarts
  Oil Capacity - without Filter 3.8 liters 4.0 quarts
  Oil Pressure - 1850 RPM 414 kPa 60 psi
Oil Pump
  Gear Diameter 38.05-38.10 mm 1.498-1.500 in
  Gear Pocket - Depth 30.52-30.58 mm 1.202-1.204 in
  Gear Pocket - Diameter 38.176-38.226 mm 1.503-1.505 in
  Gears Lash 0.094-0.195 mm 0.0037-0.0077 in
  Relief Valve-to-Bore Clearance 0.038-0.089 mm 0.0015-0.0035 in
Piston Ring End Gap
  First Compression Ring 0.15-0.36 mm 0.006-0.014 in
  Second Compression Ring 0.5-0.71 mm 0.0197-0.0280 in
  Oil Control Ring 0.25-1.02 mm 0.009-0.040 in
Piston Ring to Groove Clearance
  First Compression Ring 0.04-0.086 mm 0.002-0.0033 in
  Second Compression Ring 0.04-0.08 mm 0.002-0.0035 in
  Oil Control Ring 0.07-0.095 mm 0.0028-0.0037 in
Piston Ring Thickness
  First Compression Ring 1.164-1.190 mm 0.046-0.047 in
  Second Compression Ring 1.470-1.490 mm 0.057-0.058 in
  Oil Control Ring - Maximum 2.960 mm 0.116 in
Pistons
  Piston Diameter - New 88.986-89.024 mm 3.503-3.504 in
  Piston Ring Groove Width - Top 1.23-1.25 mm 0.048-0.049 in
  Piston Ring Groove Width - Second 1.53-1.55 mm 0.060-0.061 in
  Piston Ring Groove Width - Third 3.03-3.05 mm 0.119-0.120 in
  Piston to Bore Clearance -0.008-0.048 mm -0.0003-0.0018 in
Rocker Arms
  Valve Rocker Arm Ratio 1.6:1
Valves
  Valve Face Angle 45 degrees
  Valve Face Runout 0.050 mm 0.002 in
  Valve Seat Angle 46 degrees
  Valve Seat Depth - Intake 7.9-8.1 mm 0.311-0.318 in
  Valve Seat Depth - Exhaust 8.9-9.1 mm 0.350-0.358 in
  Valve Seat Runout 0.037 mm 0.0015 in
  Valve Seat Width - Intake 1.55-1.80 mm 0.061-0.071 in
  Valve Seat Width - Exhaust 1.70-2.0 mm 0.067-0.079 in
  Valve Stem-to-Guide Clearance 0.026-0.068 mm 0.0010-0.0027 in
  Valve Stem Diameter - Intake 7.967-7.980 mm 0.3137-0.3142 in
  Valve Stem Diameter 7.944-7.965 mm 0.3128-0.3136 in
Valve Lifters/Push Rods
  Push Rod Length - Intake 146.0 mm 5.75 in
  Push Rod Length - Exhaust 152.5 mm 6.0 in
  Valve Lifter Diameter 21.387-21.405 mm 0.8420-0.3136 in
  Valve Lifter-to-Bore Clearance 0.012-0.068 mm 0.0005-0.0027 in
Valve Springs
  Valve Spring Free Length 48.5 mm 1.89 in
  Valve Spring Installed Height 43.2 mm 1.701 in
  Valve Spring Load - Closed 320 N 43.2 mm 75 lb 1.701 in
  Valve Spring Load - Open 1036 N 32 mm 230 lb 1.260 in
  Valve Spring Total Number of Coils 6.55
RENDER: 1.0x

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