The connecting rod bearing is a crucial component in an internal combustion engine. It supports the crankshaft at the big end of the connecting rod, allowing the crankshaft to rotate smoothly under high load and speed while maintaining proper oil clearance.
Selecting the correct bearing size is essential to engine longevity and performance.
Engine Connecting Rod Bearing Size Chart
Toyota
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) 1ZZ-FE 1.484 – 1.488 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 2ZZ-GE 1.488 – 1.492 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 3F-E 1.492 – 1.496 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 1GR-FE 1.500 – 1.504 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 2TR-FE 1.500 – 1.504 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Honda
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) B16, B18 1.771 – 1.775 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 K20, K24 1.780 – 1.790 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 F20C 1.775 – 1.785 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 D-Series 1.765 – 1.775 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 H-Series 1.770 – 1.780 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Chevrolet / GM
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) Small Block 350 2.100 – 2.125 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Small Block 400 2.125 – 2.150 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 LS1 / LS2 / LS3 2.099 – 2.125 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 5.3L Vortec 2.100 – 2.120 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Duramax Diesel LB7 2.300 – 2.400 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Related Car Engine Oil Capacity Chart(Car Model A to Z)
Ford
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) 302 Windsor 2.100 – 2.125 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 351 Windsor 2.100 – 2.125 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 5.0L Coyote 2.099 – 2.125 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 6.0L Powerstroke Diesel 2.300 – 2.400 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 7.3L Powerstroke Diesel 2.300 – 2.400 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Nissan
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) SR20DET 1.968 – 1.972 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 KA24DE 1.975 – 1.984 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 RB25DET 1.984 – 1.992 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 VQ35DE 1.992 – 2.000 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 VQ37VHR 2.000 – 2.010 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Related Engine VIN Number Decoding Chart(For All Vehicle Brands)
Mitsubishi
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) 4G63 1.968 – 1.975 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 6G72 1.992 – 2.000 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 4B11 1.968 – 1.984 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 4G63T 1.968 – 1.984 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 4G64 1.984 – 2.000 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Subaru
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) EJ20 1.968 – 1.980 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 EJ25 1.980 – 1.992 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 FB20 1.968 – 1.980 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 FA20 1.980 – 1.992 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 EZ30 1.992 – 2.004 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Related Year to VIN Chart(From 1980–2069)
Mazda
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) B6 1.850 – 1.860 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 BP 1.860 – 1.870 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 FS 1.870 – 1.880 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 KL 1.880 – 1.890 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 MZR 1.890 – 1.900 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
BMW
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) M50 1.850 – 1.860 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 M52 1.860 – 1.870 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 N52 1.870 – 1.880 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 S54 1.880 – 1.890 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 B58 1.890 – 1.900 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Related Engine Oil Compatibility Chart(A Detailed Guide)
Mercedes-Benz
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) M102 1.850 – 1.860 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 M104 1.860 – 1.870 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 OM601 1.875 – 1.885 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 OM602 1.885 – 1.895 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 M271 1.890 – 1.900 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Volkswagen / Audi
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) 1.8T 1.850 – 1.860 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 2.0T FSI 1.860 – 1.870 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 2.0 TDI 1.870 – 1.880 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 VR6 1.880 – 1.890 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 3.6 FSI 1.890 – 1.900 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Related Engine Torque Calculator
Hyundai / Kia
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) Theta / Theta II 1.850 – 1.860 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Nu 1.860 – 1.870 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Gamma 1.870 – 1.880 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Lambda 1.880 – 1.890 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Smart GDI 1.890 – 1.900 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Volvo
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) B230 1.850 – 1.860 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 B5254 1.860 – 1.870 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 B5244 1.870 – 1.880 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 D5 Diesel 1.950 – 1.970 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 T5 / T6 Turbo 1.880 – 1.890 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Related Engine Displacement Calculator
Chrysler / Dodge
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) 2.7L V6 1.968 – 1.980 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 3.5L V6 1.980 – 1.992 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 5.7 HEMI 2.100 – 2.125 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 6.1 HEMI 2.100 – 2.125 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 6.4 HEMI 2.100 – 2.125 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Diesel Engines (Cummins / GM / Ford)
Engine / Series Standard Journal Dia (in) Undersize Options (in) Oversize Options (in) Typical Oil Clearance (in) Cummins 5.9L 12V 2.300 – 2.400 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Cummins 6.7L 2.350 – 2.450 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 GM Duramax LB7 2.300 – 2.400 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Ford 6.0L Powerstroke 2.300 – 2.400 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025 Ford 7.3L Powerstroke 2.300 – 2.400 -0.002, -0.005, -0.010 +0.002 0.0015 – 0.0025
Related Car Engine Oil Color Chart(Color That Signals Immediate Danger)
Color-Coded Bearing Selection
Color Bearing ID (mm) Crank Journal Diameter (mm) Target Oil Clearance (mm) White 36.000 35.970 – 35.990 0.030 Red 36.010 35.980 – 36.000 0.010 – 0.030 Blue 36.020 35.990 – 36.010 0.010 – 0.030 Green 36.030 36.000 – 36.020 0.010 – 0.030 Yellow 36.040 36.010 – 36.030 0.010 – 0.030
Generic Connecting Rod Bearing Size Chart
Bearing Type Standard Journal Diameter (in) Undersize Bearing (in) Oversize Bearing (in) Common Oil Clearance (in) Connecting Rod Bearing 1.850 1.848 (-0.002) 1.852 (+0.002) 0.0015 – 0.0025 Connecting Rod Bearing 1.845 1.843 (-0.002) 1.847 (+0.002) 0.0015 – 0.0025 Connecting Rod Bearing 1.840 1.838 (-0.002) 1.842 (+0.002) 0.0015 – 0.0025 Connecting Rod Bearing 1.835 1.833 (-0.002) 1.837 (+0.002) 0.0015 – 0.0025 Connecting Rod Bearing 1.830 1.828 (-0.002) 1.832 (+0.002) 0.0015 – 0.0025
Why Bearing Sizes Matter
When rebuilding or assembling an engine, it is necessary to measure:
Crankshaft journal diameter Connecting rod bore inside diameter
These measurements determine the correct bearing size. Bearings typically come in:
Standard size (STD) Undersize (e.g., 0.002″, 0.005″, 0.010″) Oversize (less common)
Correct bearing size ensures proper oil clearance. Oil clearance is the small gap between the crank journal and bearing, where oil forms a protective film. Typical clearances are very small, often around 0.0015″ to 0.0025″ for rod bearings in most automotive engines.
How Connecting Rod Bearing Sizes Are Defined
Bearings are designed to maintain proper oil clearance . Manufacturers often mark bearings using:
Numbers, letters, or color codes Size groups corresponding to inner diameters or thicknesses
Undersized bearings are used when crankshaft journals are ground smaller. Accurate measurement is done using micrometers, bore gauges, or plastigauge to check oil clearance after assembly.
Steps to Select Connecting Rod Bearings
Measure crankshaft journals with a micrometer.Measure the rod bore inside diameter .Determine bearing group or size code based on the manufacturer’s chart.Select STD or undersized bearing according to measurements.Check oil clearance with plastigauge after assembly.
Proper installation prevents bearing failure, low oil pressure, or crankshaft damage.
Tips for Engine Rebuilders
Clearances: Target oil clearance is usually around 0.001″ per inch of journal diameter.Markings: Letters or numbers on rods correspond to bearing size; always cross-check with the service manual.Undersized bearings: Used when journals are machined smaller; oversize bearings are rarely required.Avoid mixing sizes: Bearings in a set must match corresponding journals for all rods.
