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Engine 4.0L: Specifications: Engine

Engine Specifications

DESCRIPTION SPECIFICATION
Engine Type In-line 6 Cylinder
Bore and Stroke 98.4 x 86.69 mm (3.88 x 3.413 in.)
Displacement 4.0L (242 cu. in.)
Compression Ratio 8.8:1
Firing Order 1-5-3-6-2-4
Lubrication Pressure Feed-Full Flow Filtration
Cooling System Liquid Cooled-Forced Circulation
Cylinder Block Cast Iron
Crankshaft Cast Nodular Iron
Cylinder Head Cast Iron
Camshaft Cast Iron
Pistons Aluminum Alloy
Combustion Chamber Dual-Quench
Connecting Rods Cast Malleable Iron
CAMSHAFT 
Hydraulic Tappet Clearance Zero Lash
Bearing Clearance 0.025 to 0.076 mm (0.001 to 0.003 in.)
Bearing Journal Diameter  
No. 1 51.54 to 51.56 mm (2.029 to 2.030 in.)
No. 2 51.28 to 51.31 mm (2.019 to 2.020 in.)
No. 3 51.03 to 51.05 mm (2.009 to 2.010 in.)
No. 4 50.78 to 50.80 mm (1.999 to 2.000 in.)
Base Circle Runout (MAX) 0.03 mm (0.001 in.)
Valve Lift  
Intake 10.350 mm (0.4075 in.)
Exhaust 10.528 mm (0.4145 in.)
Valve Timing 
Intake  
Opens 12.4° BTDC
Closes 60.9° ABDC
Exhaust  
Opens 49.8 BBDC
Closes 29.2° ATDC
Valve Overlap 41.6°
Intake Duration 253.3°
Exhaust Duration 259.°
CRANKSHAFT 
End Play 0.038 to 0.165 mm (0.0015 to 0.0065 in.)
Main Bearing Journal Diameter  
No. 1-6 63.489 to 63.502 mm (2.4996 to 2.5001 in.)
No. 7 63.449 to 63.487 mm (2.4980 to 2.4995 in.)
Main Bearing Journal Width  
No. 1 27.58 to 27.89 mm (1.086 to 1.098 in.)
No. 3 32.28 to 32.33 mm (1.271 to 1.273 in.)
No. 2-4-5-6-7 30.02 to 30.18 mm (1.182 to 1.188 in.)
Main Bearing Clearance 0.03 to 0.06 mm (0.001 to 0.0025 in.)
Preferred 0.051 mm (0.002 in.)
Connecting Rod Journal Diameter 53.17 to 53.23 mm (2.0934 to 2.0955 in.)
Connecting Rod Journal Width 27.18 to 27.33 mm (1.070 to 1.076 in.)
Out-of-Round (MAX) 0.013 mm (0.0005 in.)
Taper (MAX) 0.013 mm (0.0005 in.)
CYLINDER BLOCK 
Deck Height 240.03 to 240.18 mm (9.450 to 9.456 in.)
Deck Clearance (Below Block) 0.546 mm (0.0215 in.)
Cylinder Bore Diameter  
Standard 98.45 to 98.48 mm (3.8759 to 3.8775 in.)
Taper 0.025 mm (0.001 in.)
Out-of-Round 0.025 mm (0.001 in.)
Tappet Bore Diameter 23.000 to 23.025 mm (0.9055 to 0.9065 in.)
Flatness 0.03 mm per 25 mm (0.001 in. per 1 in.)
0.05 mm per 152 mm (0.002 in. per 6 in.)
Flatness Max. 0.20 mm max. for total length
(0.008 in. max. for total length)
Main Bearing Bore Diameter 68.3514 to 68.3768 mm (2.691 to 2.692 in.)
CONNECTING ROD 
Total Weight (Less Bearing) 663 to 671 grams (23.39 to 23.67 oz.)
Length (Center-to-Center) 155.52 to 155.62 mm (6.123 to 6.127 in.)
Piston Pin Bore Diameter 23.59 to 23.62 mm (0.9288 to 0.9298 in.)
Bore (Less Bearings) 56.08 to 56.09 mm (2.2080 to 2.2085 in.)
Bearing Clearance 0.025 to 0.076 mm (0.001 to 0.003 in.)
Preferred 0.044 to 0.050 mm (0.0015 to 0.0020 in.)
Side Clearance 0.25 to 0.48 mm (0.010 to 0.019 in.)
Twist (Max.) 0.002 mm per mm (0.002 in. per inch)
Bend (Max.) 0.002 mm per mm (0.002 in. per inch.)
CYLINDER COMPRESSION PRESSURE 
Pressure Range 827 to 1,034 kPa (120 to 150 psi)
Max. Variation Between Cylinders 206 kPa (30 psi)
CYLINDER HEAD 
Combustion Chamber 55.22 to 58.22 cc (3.37 to 3.55 cu. in.)
Valve Guide I.D. (Integral) 7.95 to 7.97 mm (0.313 to 0.314 in.)
Valve Stem-to-Guide Clearance 0.025 to 0.076 mm (0.001 to 0.003 in.)
Valve Seat Angle  
Intake 44.5°
Exhaust 44.5°
Valve Seat Width 1.02 to 1.52 mm (0.040 to 0.060 in.)
Valve Seat Runout 0.064 mm (0.0025 in.)
Flatness 0.03 mm per 25 mm (0.001 in. per 1 in.)
  0.05 mm per 152 mm (0.002 in. per 6 in.)
Flatness Max. 0.20 mm - max. for total length
(0.008 in. max. for total length)
ROCKER ARMS, PUSH RODS & TAPPETS 
Rocker Arm Ratio 1.6:1
Push Rod Length (Pink) 244.856 to 245.364 mm (9.640 to 9.660 in.)
Push Rod Diameter 7.92 to 8.00 mm (0.312 to 0.315 in.)
Hydraulic Tappet Diameter 22.962 to 22.974 mm (0.904 to 0.9045 in.)
Tappet-to-Bore Clearance 0.025 to 0.063 mm (0.001 to 0.0025 in.)
VALVES 
Valve Length (Overall)  
Intake 122.479 to 122.860 mm (4.822 to 4.837 in.)
Exhaust 122.860 to 123.241 mm (4.837 to 4.852 in.)
Valve Stem Diameter 7.899 to 7.925 mm (0.311 to 0.312 in.)
Stem-to-Guide Clearance 0.025 to 0.076 mm (0.001 to 0.003 in.)
Valve Head Diameter  
Intake 48.387 to 48.641 mm (1.905 to 1.915 in.)
Exhaust 37.973 to 38.227 mm (1.495 to 1.505 in.)
Valve Face Angle  
Intake 46.5°
Exhaust 46.5°
Tip Refinishing (Max. Allowable) 0.25 mm (0.010 in.)
VALVE SPRINGS 
Free Length (Approx.) 47.65 mm (1.876 in.)
Spring Load  
Valve Closed 316 to 351 N @ 41.656 mm
(71 to 79 lbf. @ 1.64 in.)
Valve Open 898.6 to 969.7 N @ 30.89 mm
(202 to 218 lbf @ 1.216 in.)
Inside Diameter 21.0 mm to 21.51 mm (0.827 to 0.847 in.)
Installed Height 41.656 mm (1.64 in.)
PISTONS 
Weight (Less Pin) 417 to 429 grams (14.7 to 15.1 oz.)
Piston Pin Bore (Centerline to Piston Top) 40.61 to 40.72 mm (1.599 to 1.603 in.)
Piston-to-Bore Clearance 0.018 to 0.038 mm (0.0008 to 0.0015 in.)
Ring Gap Clearance  
Top Compression Ring 0.229 to 0.610 mm (0.0090 to 0.0240 in.)
2nd Compression Ring 0.483 to 0.965 mm (0.0190 to 0.0380 in.)
Oil Control Steel Rails 0.254 to 1.500 mm (0.010 to 0.060 in.)
Ring Side Clearance  
Compression Rings 0.042 to 0.084 mm (0.0017 to 0.0033 in.)
Oil Control Rings 0.06 to 0.21 mm (0.0024 to 0.0083 in.)
Piston Ring Groove Height  
Compression Rings 1.530 to 1.555 mm (0.0602 to 0.0612 in.)
Oil Control Ring 4.035 to 4.060 mm (0.1589 to 0.1598 in.)
Piston Ring Groove Diameter  
No.1 Compression Ring 88.39 to 88.65 mm (3.48 to 3.49 in.)
No.2 Compression Ring 87.63 to 87.88 mm (3.45 to 3.46 in.)
Oil Control Ring 89.66 to 89.92 mm (3.53 to 3.54 in.)
Piston Pin Bore Diameter 23.650 to 23.658 mm (0.9312 to 0.9315 in.)
Piston Pin Diameter 23.637 to 23.640 mm (0.9306 to 0.9307 in.)
Piston-to-Pin Clearance 0.0102 to 0.0208 mm (0.0005 to 0.0009 in.)
Piston-to-Pin Connecting Rod (Press Fit) 8.9 kN (2000 lbf.)
OIL PUMP 
Gear-to-Body Clearance (Radial) 0.051 to 0.102 mm (0.002 to 0.004 in.)
Gear-to-Body Clearance (Radial) Preferred 0.051 mm (0.002 in.)
Gear End Clearance Plastigage 0.051 to 0.152 mm (0.002 to 0.006 in.)
Gear End Clearance Plastigage (Preferred) 0.051 mm (0.002 in.)
Gear End Clearance Feeler Gauge 0.1016 to 0.2032 mm (0.004 to 0.008 in.)
Gear End Clearance Feeler Gauge (Preferred) 0.1778 mm (0.007 in.)
Oil Pressure 
At Idle Speed 89.6 kPa (13 psi)
At 1600 rpm & Higher 255 to 517 kPa (37 to 75 psi)
Oil Pressure Relief 517 kPa (75 psi)