Engine Mechanical Specifications. GMC Truck GMC K Sierra

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2003 🢒 GMC K Sierra - 4WD 🢒 Engine 🢒 Engine Mechanical - 8.1L 🢒 Engine Mechanical Specifications

Application	Specification
Application	Metric	English
General
Engine Type	V-8
Displacement	8.1L	496 CID
RPO	L18
VIN	G
Bore	107.950 mm	4.250 in
Stroke	111.00 mm	4.370 in
Compression Ratio	9.1:1
Firing Order	1-8-7-2-6-5-4-3
Spark Plug Gap	1.52 mm	0.060 in
Block
Crankshaft Main Bearing Bore Diameter	74.6060-74.6220 mm	2.9372-2.9379 in
Cylinder Bore Diameter - Production	107.950-107.968 mm	4.2500-4.2507 in
Cylinder Bore Diameter - Service	107.940-107.990 mm	4.2496-4.2516 in
Cylinder Bore Out-of-Round - Production, Maximum Minus Minimum Bore Diameter	0.0180 mm	0.0007 in
Cylinder Bore Out-of-Round - Service, Maximum Minus Minimum Bore Diameter	0.050 mm	0.002 in
Cylinder Bore Taper - Production	0.0180 mm	0.0007 in
Cylinder Bore Taper - Service Thrust Axis	0.050 mm	0.002 in
Cylinder Bore Taper - Service Pin Axis	0.050 mm	0.002 in
Cylinder Head Deck Height - from Centerline of Crankshaft	259.875-260.125 mm	10.231-10.241 in
Cylinder Head Deck Surface Flatness - Entire Face	0.100 mm	0.004 in
Cylinder Head Deck Surface Flatness - Within 150 mm (6 in)	0.050 mm	0.002 in
Valve Lifter Bore Diameter	21.417-21.443 mm	0.843-0.844 in
Camshaft
Camshaft Bearing Inside Diameter	49.5480-49.5730 mm	1.9507-1.9517 in
Camshaft Journal Diameter	49.4720-49.5220 mm	1.9477-1.9497 in
Camshaft Lobe Lift - Exhaust	6.973-7.075 mm	0.2745-0.2785 in
Camshaft Lobe Lift - Intake	6.924-7.026 mm	0.2726-0.2766 in
Camshaft Runout - Production	0.051 mm	0.002 in
Camshaft Runout - Service	0.076 mm	0.003 in
Connecting Rod
Connecting Rod Bearing Clearance - Production	0.021-0.064 mm	0.0008-0.0025 in
Connecting Rod Bearing Clearance - Service	0.021-0.081 mm	0.0008-0.0032 in
Connecting Rod Side Clearance	0.384-0.686 mm	0.0151-0.0270 in
Crankshaft
Connecting Rod Journal Diameter	55.854-55.870 mm	2.1990-2.1996 in
Connecting Rod Journal Out-of-Round - Production	0.0102 mm	0.0004 in
Connecting Rod Journal Taper - Production	0.0102 mm	0.0004 in
Crankshaft End Play	0.127-0.279 mm	0.0050-0.0110 in
Crankshaft Main Bearing Clearance - #1, #2, #3, #4 Production	0.022-0.052 mm	0.0008-0.0020 in
Crankshaft Main Bearing Clearance - #5 Production	0.035-0.067 mm	0.0014-0.0026 in
Crankshaft Main Bearing Clearance - #1, #2, #3, #4 Service	0.022-0.089 mm	0.0008-0.0035 in
Crankshaft Main Bearing Clearance - #5 Service Limit	0.035-0.102 mm	0.0014-0.0040 in
Crankshaft Main Journal Diameter	69.805-69.822 mm	2.7482-2.7489 in
Crankshaft Main Journal Out-of-Round - Production	0.0102 mm	0.0004 in
Crankshaft Main Journal Taper - Production	0.0102 mm	0.0004 in
Crankshaft Runout - Production	0.0380 mm	0.0015 in
Crankshaft Runout - Service	0.0510 mm	0.0020 in
Cylinder Head
Cylinder Head Height/Thickness	259.875-260.125 mm	10.231-10.241 in
Surface Flatness - Block Deck	0.050 mm	0.002 in
Surface Flatness - Exhaust Manifold Deck	0.102 mm	0.004 in
Surface Flatness - Intake Manifold Deck	0.080 mm	0.003 in
Exhaust Manifold
Surface Flatness	0.254 mm	0.010 in
Lubrication System
Oil Capacity - Without Filter	5.7L	6 Qts
Oil Pressure - Minimum	34 kPa @ 1,000 RPM	5 psi @ 1,000 RPM
Oil Pressure - Minimum	69 kPa @ 2,000 RPM	10 psi @ 2,000 RPM
Piston Rings
Piston Ring End Gap
First Compression Ring - Production	0.300-0.450 mm	0.012-0.018 in
First Compression Ring - Service	0.450-0.675 mm	0.018-0.027 in
Second Compression Ring - Production	0.450-0.650 mm	0.017-0.025 in
Second Compression Ring - Service	0.675-0.975 mm	0.026-0.039 in
Oil Control Ring - Production	0.249-0.759 mm	0.0098-0.0299 in
Oil Control Ring - Service	0.373-1.138 mm	0.015-0.045 in
Piston Ring to Groove Clearance
First Compression Ring	0.031-0.074 mm	0.0012-0.0029 in
Second Compression Ring	0.031-0.074 mm	0.0012-0.0029 in
Oil Control Ring	0.051-0.203 mm	0.002-0.008 in
Piston and Pins
Piston
Piston Diameter	Not Measurable	Not Measurable
Piston to Bore Clearance	Interference Fit	Interference Fit
Pin
Piston Pin Clearance to Connecting Rod Bore	0.049-0.020 mm Interference	0.00019-0.0007 in Interference
Piston Pin Diameter	26.416-26.419 mm	1.0400-1.0401 in
Valve System
Valves
Valve Face Angle - Exhaust	45 degrees
Valve Face Angle - Intake	45 degrees
Valve Head Diameter - Exhaust	43.69 mm	1.72 in
Valve Head Diameter - Intake	55.63 mm	2.19 in
Valve Lash - Exhaust	Net Lash	Net Lash
Valve Lash - Intake	Net Lash	Net Lash
Valve Seat Angle - Exhaust	46 degrees
Valve Seat Angle - Intake	46 degrees
Valve Seat Runout - Exhaust	0.0500 mm	0.002 in
Valve Seat Runout - Intake	0.0500 mm	0.002 in
Valve Seat Width - Exhaust	1.651-2.159 mm	0.060-0.095 in
Valve Seat Width - Intake	0.800-1.200 mm	0.030-0.060 in
Valve Stem Diameter - Exhaust	9.431-9.449 mm	0.3713-0.3720 in
Valve Stem Diameter - Intake	9.436-9.454 mm	0.3715-0.3722 in
Valve Stem-to-Guide Clearance - Production Exhaust	0.030-0.079 mm	0.0012-0.0031 in
Valve Stem-to-Guide Clearance - Production Intake	0.025-0.074 mm	0.0010-0.0029 in
Valve Stem-to-Guide Clearance - Service Exhaust	0.030-0.091 mm	0.0012-0.0036 in
Valve Stem-to-Guide Clearance - Service Intake	0.025-0.088 mm	0.0010-0.0034 in
Rocker Arms
Valve Rocker Arm Ratio	1.70:1
Valve Springs
Valve Spring Free Length	56.35 mm	2.218 in
Valve Spring Installed Height	45.923-46.685 mm	1.808-1.838 in
Valve Spring Load - Closed	381-419 N·m @ 45.923 mm	86-94 lb @ 1.808 in
Valve Spring Load - Open	962-1058 N·m @ 33.985 mm	216-236 lb @ 1.338 in