Product Description
Interstate-McBee M-3910260 Bell Housing Adapter Plug O-Ring – 1989–2002 5.9L Cummins
Replacement O-ring for the bell housing adapter plug on 5.9L Cummins B-series engines. Restores a proper seal to prevent fluid seepage at the adapter plug location. Sold individually.
- Direct replacement: Matches the form and fit of the original seal for a leak-free install.
- Engineered for service: Correct cross-section and diameter for the bell housing adapter plug groove.
- Broad coverage: Fits 12-valve (1989–1998) and 24-valve (1998.5–2002) 5.9L Cummins applications where this seal is specified.
- Value: Interstate-McBee quality at an aftermarket price point.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-3910260 |
| OEM Reference | Cummins 3910260 |
| Sold As | Each (1 O-ring) |
| Position | Bell housing adapter plug – O-ring |
What’s Included
- (1) O-ring, P/N M-3910260
Vehicle/Engine Fitment
Always verify by engine serial number (ESN) or parts catalog for your specific build.
- Dodge Ram 2500/3500 with 5.9L Cummins B-series
- Model Years: 1989–1998 (12-valve), 1998.5–2002 (24-valve)
- Other B-series applications where Cummins 3910260 is specified.
Install Notes
- Clean the groove and mating surfaces; remove old seal material and debris.
- Lightly lubricate the new O-ring with clean engine oil or approved assembly lube.
- Do not twist or stretch excessively; seat evenly in the groove.
- Torque the plug per the applicable Cummins/Dodge service manual. Do not use sealant unless specified by the manual.
Why Buy From CPP Diesel
- Knowledgeable diesel support with ESN-verified fitment
- Fast shipping and easy returns
- Wide selection of complementary B-series gaskets and seals
FAQ
Does this fit both 12-valve and 24-valve 5.9L Cummins?
Yes—this O-ring covers 1989–2002 5.9L Cummins applications where Cummins 3910260 is used. Verify by ESN for edge cases.
How many do I need?
One O-ring per bell housing adapter plug. This listing is for a single O-ring.
Is the adapter plug included?
No—this listing is the O-ring only. Reuse your plug if serviceable or purchase a new plug separately.
