TORQUE SPECS FOR CUMMINS B3.9, B4.5, B4.5 RGT & 5.9L

March 27, 2023

Cummins B3.9, B4.5, B4.5 RGT, and 5.9L Torque Specs: Essential Information for Maintenance

The Cummins B3.9, B4.5, B4.5 RGT, and 5.9L engines are renowned for their efficiency and reliability across various industries. Whether used in industrial machinery, agricultural equipment, or commercial vehicles, maintaining these engines requires precise torque specifications for optimal performance. In this guide, we provide the crucial torque specs to ensure your Cummins engines operate smoothly and deliver long-term reliability.

Cylinder Head Torque Specs for Cummins B series Engines

PART/MATERIAL/COLOR	LENGTH	TORQUE VALUE IN NM [ FT-LB ]
CYLINDER HEAD CAPSCREWS (4-CYLINDER ENGINE ALL CAPSCREWS)	N/A	90 N•M [ 66 FT-LB ]

NOTE: On a four-cylinder engine, capscrew number 1 is located in between cylinders 2 and 3. The numbered sequence is the same as a six cylinder but stops at capscrew number 18.

Torque Specs 4 Cylinder Engine

Cylinder Head &Related Components For Cummins 4B 3.9L Engine

Cylinder Head & Related Components For Cummins 4BT 3.9L Engine

Cylinder Head & Related Components For Cummins 4BTA 3.9L Engine

Cylinder Head & Related Components For Cummins 6B 5.9L Engine

Cylinder Head & Related Components For Cummins 6BT 5.9L Engine

Cylinder Head & Related Components For Cummins 6BTA 5.9L Engine

Cylinder Head & Related Components For Cummins ISB 4.5 L Engine

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

CYLINDER HEAD CAPSCREWS (6-CYLINDER ENGINE ALL CAPSCREWS)	N/A	90 N•M [ 66 FT-LB ]
CYLINDER HEAD CAPSCREWS (4-CYLINDER ENGINE, LONG CAPSCREWS NUMBERS 4, 5, 12, & 13)	N/A	120 N•M [ 89 FT-LB ]
CYLINDER HEAD CAPSCREWS (6-CYLINDER ENGINE, LONG CAPSCREWS NUMBERS 4, 5, 12, 13, 20, & 21)	N/A	120 N•M [ 89 FT-LB ]

Torque Specs CYLINDER HEAD CAPSCREWS (6-CYLINDER ENGINE ALL CAPSCREWS)

Cylinder Head & Related Components For Cummins ISB 5.9 L Engine

Cylinder Head & Related Components For Cummins ISB 6.7 L Engine

Cylinder Head & Related Components For Cummins QSB 4.5 L Engine

Cylinder Head & Related Components For Cummins QSB 5.9 L Engine

Cylinder Head & Related Components For Cummins QSB 6.7 L Engine

Cylinder Head & Related Components For Cummins QSB 7.0 L Engine

Piston & Connecting Rod Assembly Torque Specs for Cummins B series Engines

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

CONNECTING ROD CAPSCREWS (INITIAL)

N/A

35 N•M [ 26 FT-LB ]

CONNECTING ROD CAPSCREWS (INITIAL)

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

CONNECTING ROD CAPSCREWS (B3.9, B4.5 & B5.9)	N/A	1. 45 N•M [ 33 FT-LB ] 2. TURN 90 DEGREES CLOCKWISE.
CONNECTING ROD CAPSCREWS (B4.5)	N/A	1. 25 N•M [ 221 IN-LB ] 2. TURN 60 DEGREES CLOCKWISE.

Piston & Connecting Rod Assembly Torque Specs for Cummins B series Engine

CONNECTING ROD CAPSCREWS (B3.9, B4.5 & B5.9)

Connecting Rod Assembly and related Components For Cummins 4B Engine

Connecting Rod Assembly and related Components For Cummins 4BT Engine

Connecting Rod Assembly and related Components For Cummins 4BTA Engine

Connecting Rod Assembly and related Components For Cummins 6B Engine

Connecting Rod Assembly and related Components For Cummins 6BT Engine

Connecting Rod Assembly and related Components For Cummins 6BTA Engine

Connecting Rod Assembly and related Components For Cummins ISB 4.5l Engine

Connecting Rod Assembly and related Components For Cummins ISB 5.9L Engine

Connecting Rod Assembly and related Components For Cummins ISB 6.7L Engine

Connecting Rod Assembly and related Components For Cummins QSB 4.5 Engine

Connecting Rod Assembly and related Components For Cummins QSB 5.9 Engine

Connecting Rod Assembly and related Components For Cummins QSB 6.7 Engine

Connecting Rod Assembly and related Components For Cummins QSB 7.0 Engine

Crankshaft Torque Specs for Cummins B series Engines

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

CRANKSHAFT BEARING CAPSCREWS (INITIAL)

N/A

50 N•M [ 37 FT-LB ]

CRANKSHAFT BEARING CAPSCREWS (INITIAL)

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

CRANKSHAFT BEARING CAPSCREWS (B3.9, B4.5, & B5.9 ENGINES)	N/A	1. 60 N•M [ 44 FT-LB ] 2. 90 N•M [ 66 FT-LB ] 3. TURN ALL CAPSCREWS THROUGH 90 DEGREES.
CRANKSHAFT BEARING CAPSCREWS (B4.5 ENGINES W/ PREVIOUSLY INSTALLED MAIN BEARING CAPSCREWS)	N/A	1. 60 N•M [ 44 FT-LB ] 2. 80 N•M [ 59 FT-LB ] 3. ROTATE 90 DEGREES.
CRANKSHAFT BEARING CAPSCREWS (B4.5 ENGINES W/ NEW MAIN BEARING CAPSCREWS)	N/A	1. 120 N•M [ 89 FT-LB ] 2. LOOSEN COMPLETELY. 3. 60 N•M [ 44 FT-LB ] 4. 85 N•M [ 63 FT-LB ] 5. ROTATE 120 DEGREES.

CRANKSHAFT BEARING CAPSCREWS (B3.9, B4.5, & B5.9 ENGINES)

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

CRANKSHAFT BEARING CAP CAPSCREWS

N/A

176 N•M [ 130 FT-LB ]

CRANKSHAFT BEARING CAP CAPSCREWS

Fuel Injection Pump (Inline) Torque Specs for Cummins B series Engines

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

FUEL INJECTION PUMP RETAINING NUT AND WASHER

N/A

10 to 15 N•M [ 89 – 133 IN-LB ]

FUEL INJECTION PUMP RETAINING NUT AND WASHER

Fuel Injection Pump & related Components For Cummins 4B Engine

Fuel Injection Pump & related Components For Cummins 4BT Engine

Fuel Injection Pump & related Components For Cummins 4BTA Engine

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

FUEL INJECTION PUMP TIMING PLUG

N/A

27 N•M [ 20 FT-LB ]

FUEL INJECTION PUMP TIMING PLUG

Fuel Injection Pump & related Components For Cummins 6B Engine

Fuel Injection Pump & related Components For Cummins 6BT Engine

Fuel Injection Pump & related Components For Cummins 6BTA Engine

PART/MATERIAL/COLOR

LENGTH

TORQUE VALUE IN NM [ FT-LB ]

FUEL INJECTION PLUG DRIVE NUT (“A” PUMP)	N/A	1. 85 N•M [ 63 FT-LB ]
FUEL INJECTION PLUG DRIVE NUT (P3000 & P7100)	N/A	1. 195 N•M [ 144 FT-LB ]
FUEL INJECTION PLUG DRIVE NUT (NIPPONDENSO)	N/A	1. 123 N•M [ 91 FT-LB ]