Product Description
Interstate-McBee M-3901020 Piston Cooling Nozzle – 1989–1993 5.9L Cummins (Aftermarket Replacement)
Direct-fit piston cooling nozzle (oil squirter) for the early 5.9L Cummins 12-valve (6BT). These nozzles direct pressurized engine oil to the underside of the piston to reduce temperatures and improve durability. Sold individually.
- OE-style performance: Built to match Cummins reference 3901020 for proper flow and spray pattern.
- Restore reliability: Replaces clogged, damaged, or leaking factory nozzles.
- Quality materials: Interstate-McBee aftermarket replacement engineered for longevity and value.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-3901020 |
| OEM Reference | Cummins 3901020 |
| Function | Piston cooling (oil squirter/nozzle) |
| Sold As | Each (1 nozzle) |
| Typical Quantity Required | 6 nozzles (one per cylinder) |
| Position | Engine block, cylinder oil gallery |
What’s Included
- (1) Piston cooling nozzle, P/N M-3901020
Vehicle Fitment
Always verify by engine serial number (ESN) when possible.
- Dodge Ram 2500/3500 with 5.9L Cummins 12-valve (6BT)
- Model Years: 1989–1993
- Other B-Series applications calling for Cummins 3901020 (confirm by ESN and service manual).
Recommended/Related Parts
- Oil gallery sealing hardware (bolts/seals) as required by your service manual
- Engine oil & filter (for post-service oil change)
- Pan gasket and RTV (if removing the oil pan during service)
Install Notes
- Follow Cummins service procedures for access, fastener torque, and nozzle orientation.
- Inspect the old nozzle for debris; check oil passages for cleanliness.
- Prime the lubrication system and verify oil pressure after installation.
Why Buy From CPP Diesel
- ESN-verified fitment support from diesel specialists
- Fast shipping, easy returns, competitive pricing
- Deep inventory of complementary 6BT service parts
FAQ
How many do I need?
Typically six—one per cylinder. Nozzles are sold individually.
Do these include bolts or seals?
No. Reuse or replace hardware per the service manual. Inspect seals and replace as needed.
Will this fit 1994–1998 12-valve or 24-valve engines?
This listing targets 1989–1993 12-valve applications. Later engines may use different part numbers—verify by ESN.
