Standard Procedure - Connecting Rod Bearing And Crankshaft Journal Clearance
WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
- Measure the connecting rod bore with bearings removed and the bolts tightened to 100 N.m (73 ft. lbs.).
- Measure the connecting rod bore with the bearings installed and the bolts tightened to 100 N.m (73 ft. lbs.).
- Measure within 20° arc from each side of the parting line. Also measure 90° from parting line.
- Record the smallest and largest diameter.
- Measure the diameter of the rod journal at the location shown in illustration. Calculate the average diameter for each side of the journal.
- Determine minimum bearing clearance by calculating the difference between the smallest connecting rod bore diameter with the bearing installed and the average diameter for each side of the crankshaft connecting rod journal. See charts below.
- Determine the maximum bearing clearance by calculating the difference between the largest connecting rod bore diameter and the average diameter with the bearing installed for each side of the crankshaft connecting rod journal. See charts below.
- If the crankshaft is within limits, replace the bearing. If the crankshaft is out of limits, grind the crankshaft to the next smaller size and use oversize rod bearings.
CONNECTING ROD BORE DIAMETER LIMITS
| DESCRIPTION | MEASUREMENT |
|---|---|
| CONNECTING ROD BORE, BEARINGS REMOVED | MIN. 72.99 mm (2.874 in.) |
| MAX. 73.01 mm (2.875 in.) | |
| CONNECTING ROD BORE, BEARINGS INSTALLED | MIN. 69.05 mm (2.719 in.) |
| MAX. 69.10 mm (2.720 in.) |
CONNECTING ROD JOURNAL DIAMETER LIMITS
| DESCRIPTION | MEASUREMENT |
|---|---|
| CRANKSHAFT ROD JOURNAL DIAMETER | Min. 68.96 mm (2.715 in.) |
| Max. 69.01 mm (2.717 in.) | |
| BEARING CLEARANCE | Min. 0.04 mm (.002 in.) |
| Max. 0.12 mm (0.005 in.) |