Product Description
Interstate-McBee M-4892797 Lower Connecting Rod Bearing – .030" (.75 mm) Undersize
Aftermarket replacement lower rod bearing for 2003–2018 Cummins ISB 5.9L/6.7L applications. Designed for engines with a .030" (.75 mm) undersize crankshaft rod journal (post-grind). Sold individually (lower half only).
- Correct undersize: .030" (.75 mm) to match crankshaft ground to this dimension.
- Direct fit: Built to OE form/fit for ISB 5.9L and 6.7L rod big-end dimensions.
- Service friendly: Replace as part of a complete rod bearing set during overhaul or in-frame service.
- Interstate-McBee quality: Reliable aftermarket choice for work, towing, and daily duty cycles.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-4892797 |
| Component | Lower connecting rod bearing (single half) |
| Undersize | .030" (.75 mm) |
| Position | Connecting rod journal – lower shell |
| Sold As | Each (1 lower half) |
| Qty Required (per engine) | 6 lowers (one per cylinder) — typically replaced as complete upper/lower pairs |
Vehicle/Engine Fitment
Verify by engine serial number (ESN) and crankshaft grind size before ordering.
- Cummins ISB 5.9L — 2003–2007 Dodge Ram 2500/3500 applications
- Cummins ISB 6.7L — 2007.5–2018 Dodge/Ram 2500/3500 applications
- Other ISB/QSB variants that specify this part number and undersize (confirm by ESN)
What’s Included
- (1) Lower connecting rod bearing, .030" (.75 mm) undersize
Recommended/Related Parts
- Matching upper rod bearing shell in .030" (.75 mm) undersize (order separately)
- Rod bolts/nuts if torque-to-yield or if service history is unknown
- Assembly lube and plastigage for clearance verification
- Engine oil & filter for post-service change
Install Notes
- Confirm crankshaft rod journal size is .030" (.75 mm) undersize on all journals being serviced.
- Replace bearings in upper/lower pairs and keep shells with their original connecting rods/caps.
- Cleanliness matters: blow out oil passages and keep debris away from bearing surfaces.
- Lubricate bearing faces during assembly; verify oil hole alignment and tang seating.
- Torque rod bolts to spec in stages; check bearing clearance with plastigage or mic/ID bore gauge.
- Rotate engine by hand after assembly to verify free movement with no binding.
FAQ
Is this the correct size for my engine?
Only if your crank rod journals are ground to .030" (.75 mm) undersize. Measure each journal or confirm with your machine shop.
Do I need the upper shell too?
Yes. Rod bearings should be replaced as matched upper/lower pairs in the same undersize.
How many do I need?
Six lowers for a 6-cylinder engine (and six matching uppers). Order extras if you want spares.
Will this fit both 5.9L and 6.7L ISB?
Yes—when specified by ESN and provided the crank is .030" (.75 mm) undersize. Always verify by ESN and parts catalog.
Why Buy From CPP Diesel
- Diesel-specialist support with ESN verification
- Fast shipping and easy returns
- Huge selection of ISB overhaul and service parts
