This procedure covers removal, inspection, and replacement of connecting rod bearings on the 3.5L EcoBoost V6 engine, requiring engine removal and complete disassembly.

Warnings

Tools required

Parts

• Connecting rod bearing set (standard or appropriate oversize) × 1 — Use OEM specification
• Connecting rod bolts (torque-to-yield, must be replaced) × 12 — Use OEM specification
• Engine oil and filter × 1 — FL910S or equivalent
• Oil pan gasket × 1 — Use OEM specification
• Timing chain cover gasket × 1 — Use OEM specification
• Valve cover gaskets × 2 — Use OEM specification
• Crankshaft seal (front) × 1 — Use OEM specification
• RTV silicone sealant (Motorcraft TA-357) × 1 — TA-357
• Engine assembly lubricant × 1 — Use OEM specification

Fluids

• Motorcraft 0W-20 Full Synthetic — 6 qt
• Motorcraft Orange Coolant — 13 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Disconnect negative battery cable and wait 5 minutes for airbag system discharge
3. Drain engine coolant completely into appropriate container
4. Drain engine oil and remove oil filter
5. Remove engine cover and air intake system
6. Relieve fuel system pressure by removing fuel pump fuse and running engine until it stalls
7. Tag and photograph all electrical connectors, vacuum lines, and hoses before disconnection
8. Remove turbochargers, exhaust manifolds, and intercooler piping
9. Disconnect all wiring harnesses from engine
10. Remove radiator, cooling fans, and all coolant hoses
11. Disconnect transmission from engine and support transmission with jack
12. Remove engine mount bolts and attach engine hoist with proper lifting brackets
13. Remove engine from vehicle and mount securely on engine stand
14. Prepare clean workspace with adequate lighting and organization trays for hardware

Procedure

1. 1

   Remove valve covers and timing components
   Remove both valve covers, then remove timing chain cover. Remove timing chains, guides, and tensioners following proper timing chain procedure. Mark timing positions before removal. Remove camshafts from both cylinder heads.
2. 2

   Remove cylinder heads
   Remove cylinder head bolts in reverse of tightening sequence. Lift cylinder heads off engine block and place on clean surface with combustion chambers facing up. Keep head bolts organized by position if reusing.
3. 3

   Remove oil pan and oil pump
   Remove oil pan bolts and carefully separate pan from engine block. Remove oil pickup tube. Remove oil pump mounting bolts and withdraw oil pump assembly. Inspect oil pump pickup screen for debris.
4. 4

   Mark and identify connecting rods
   Verify that each connecting rod and cap are numbered 1-6 from front to back. If not clearly marked, use permanent marker to number them on the side facing the adjacent cylinder. Note orientation - numbers should be on the same side. Rotate crankshaft to bring each piston to bottom dead center before removing.
5. 5

   Remove connecting rod caps
   Starting with cylinder 1, remove both connecting rod bolts completely and discard (torque-to-yield design). Carefully remove rod cap and lower bearing shell. Keep cap with its matching rod. Push piston and rod assembly up and out through top of cylinder bore. Repeat for all six cylinders, keeping all components organized by cylinder number.
   ⚠Place clean shop rags in the bottom of cylinders as you remove pistons to prevent debris from entering crankcase.
6. 6

   Inspect crankshaft journals
   Clean all connecting rod journals thoroughly with solvent and lint-free cloth. Inspect each journal for scoring, discoloration, or damage. Measure each journal diameter at multiple points using a micrometer. Specification is 2.0861-2.0868 inches (53.0-53.02mm). Out-of-round must not exceed 0.0002 inch. Record all measurements.
7. 7

   Inspect connecting rods and pistons
   Remove upper bearing shells from connecting rods. Inspect rod small end bushings for wear. Check rod side clearance specification (should be 0.006-0.014 inch when assembled). Inspect piston skirts, ring grooves, and pin bores. Clean all carbon deposits from piston tops and ring grooves.
8. 8

   Measure bearing clearances with Plastigage
   Install new upper bearing shells (without assembly lube) in connecting rods. Place rod and piston assemblies back on their respective journals. Place strips of Plastigage across each crankshaft journal parallel to crankshaft centerline. Install lower bearing shells in caps (dry, no lube). Install caps with NEW connecting rod bolts hand-tight only. Torque bolts to Step 1 specification (18 lb-ft) and Step 2 (33 lb-ft) only - do NOT apply the final 90-degree rotation yet.
   ⚠Do not rotate crankshaft with Plastigage installed. This will give false readings.
   Torque spec

   Connecting Rod Bolts25 Nm (18 lb-ft) + 90°
9. 9

   Check bearing clearance measurements
   Remove rod caps carefully without rotating crankshaft. Measure the flattened Plastigage using the gauge on the package envelope. Acceptable clearance is 0.0009-0.0019 inch (0.023-0.048mm). If clearance is too tight (less than 0.0009), verify correct bearing size. If clearance is too loose (more than 0.0019), undersize bearings or crankshaft grinding is required. Record clearances for all six rods.
   ⚠️If any bearing clearance is out of specification, do not proceed with assembly. Engine failure will result.
10. 10

    Prepare bearings and rods for final assembly
    Remove all Plastigage residue completely with solvent. Clean all bearing surfaces and journals again with lint-free cloth. Apply thin coat of engine assembly lubricant to all bearing surfaces (both upper and lower shells) and crankshaft journals. Install upper bearing shells in connecting rods, ensuring locating tabs are properly seated.
11. 11

    Install piston and rod assemblies
    Coat piston rings and cylinder walls with engine oil. Verify ring gaps are properly positioned (staggered 120 degrees apart). Install piston ring compressor on piston. Guide connecting rod down into cylinder bore with rod bearing facing correct direction (numbers toward adjacent cylinder). Gently tap piston down through ring compressor into bore. Guide rod onto crankshaft journal. Repeat for all six cylinders in sequence.
12. 12

    Install connecting rod caps and torque bolts
    Install lower bearing shells in each rod cap, ensuring proper orientation and locating tab engagement. Install rod caps on correct rods with numbers aligned and facing proper direction. Install NEW connecting rod bolts and tighten in three-step sequence: Step 1 to 18 lb-ft, Step 2 to 33 lb-ft, then Step 3 rotate additional 90 degrees using angle gauge. Verify crankshaft rotates freely after each rod cap is installed. Check rod side clearance (0.006-0.014 inch) after installation.
    ⚠️Only use NEW connecting rod bolts. Never reuse torque-to-yield fasteners.
    Torque spec

    Connecting Rod Bolts25 Nm (18 lb-ft) + 90°
13. 13

    Install oil pump and oil pan
    Lubricate oil pump gears with engine oil and install oil pump assembly to engine block. Install pickup tube with new O-ring. Clean oil pan and block mating surfaces thoroughly. Install new oil pan gasket and apply small bead of RTV sealant at corners where gasket meets timing cover. Install oil pan and torque bolts to specification.
    Torque spec

    Gasket Bolts23 Nm (17 lb-ft)
14. 14

    Reinstall cylinder heads and timing components
    Install new head gaskets with proper orientation. Reinstall cylinder heads and torque head bolts following proper sequence and specification. Reinstall camshafts with proper timing alignment. Install timing chains, guides, and tensioners following timing chain procedure. Install new timing chain cover gasket and seal, then install cover. Install valve covers with new gaskets.
    Torque spec

    Cover Bolts19 Nm (14 lb-ft)
15. 15

    Reinstall engine and reconnect all systems
    Remove engine from stand and use hoist to reinstall engine in vehicle. Reconnect transmission and install engine mount bolts to specification. Reconnect all wiring harnesses, vacuum lines, fuel lines, and coolant hoses per documentation taken during disassembly. Reinstall turbochargers, exhaust components, and intercooler piping. Install new oil filter and fill engine with correct quantity of fresh Motorcraft 0W-20 synthetic oil. Fill cooling system with proper 50/50 mix of Motorcraft Orange coolant. Reinstall air intake system and engine cover.
    Torque spec

    Mounting Bolts31 Nm (23 lb-ft)

Reassembly

1. Double-check all electrical connections are secure and properly routed
2. Verify all coolant hoses and clamps are tight
3. Confirm oil drain plug is tight and oil filter is properly installed
4. Ensure all exhaust connections are sealed and bolted properly
5. Verify turbocharger oil feed and drain lines are connected and tight

Verification

• Reconnect battery and verify no warning lights are present on instrument cluster
• Check engine oil level on dipstick and adjust if necessary
• Prime oil system by cranking engine with fuel pump fuse removed until oil pressure is indicated
• Reinstall fuel pump fuse and start engine, monitoring for proper oil pressure immediately
• Allow engine to reach operating temperature while monitoring for leaks, unusual noises, or vibrations
• Check for any coolant, oil, or exhaust leaks around all disturbed components
• Perform test drive and monitor engine performance, oil pressure, and temperature
• After first 50 miles, recheck oil level and inspect for any leaks
• Change oil and filter after 500 miles of break-in operation

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