Product Description
Interstate-McBee M-3926126 Rear Main Crankshaft Seal w/ Wear Sleeve – 1989–2018 5.9L / 6.7L Cummins
Premium aftermarket rear main crankshaft seal kit for B-Series Cummins engines. Includes the seal and wear sleeve to restore a proper sealing surface on high-mileage or grooved crankshafts. Sold individually.
- Complete kit: Rear main seal + wear sleeve for a long-lasting repair.
- OE-style fit: Designed to match factory form and function.
- Reduced leaks: Refreshes the crank sealing surface to help stop rear main oil leaks.
- Built for service: Interstate-McBee quality components for dependable results.
Specifications
| Brand | Interstate-McBee |
| Part Number | M-3926126 |
| OEM Reference | Cummins 3926126 (reference only) |
| Contents | Rear main crankshaft seal, wear sleeve |
| Position | Rear main (crankshaft to engine block) |
| Sold As | Each (1 kit) |
Vehicle / Engine Fitment
Always confirm by engine serial number (ESN) or factory parts catalog.
- 5.9L Cummins B-Series (1989–2007)
- 6.7L Cummins B-Series (2007.5–2018)
- Common applications include Dodge/Ram 2500 & 3500 pickup platforms within the model years above, plus other B-Series industrial and medium-duty uses where the listed OE reference applies.
What’s Included
- (1) Rear main crankshaft seal
- (1) Wear sleeve
Recommended / Related Parts
- Rear main seal installer/driver tool (application-specific)
- Oil pan gasket or RTV (if pan removal is required for your procedure)
- Rear cover gasket or sealant (as applicable)
- Engine oil & filter (for post-repair service)
Install Notes
- Follow the Cummins service manual for your exact ESN. Procedures, installer tools, and torque specs vary by year/engine.
- Inspect the crank flange and rear cover for damage or grooves; install the included wear sleeve per instructions if required.
- Do not nick or roll the seal lip during installation; use the proper alignment/installer tool.
- Some seals are designed for dry installation (no oil on the sealing lip). Follow the instructions for your exact seal material.
- Verify crankcase ventilation is functioning; excess crankcase pressure can cause repeat leaks.
Why Buy From CPP Diesel
- Diesel specialists with ESN-verified fitment support
- Fast shipping and competitive pricing
- Deep inventory of complementary Cummins B-Series parts
FAQ
Does this kit include the wear sleeve?
Yes. The M-3926126 kit includes both the rear main seal and a wear sleeve.
How do I know if I need the sleeve?
If the crank sealing surface shows grooves or wear, install the sleeve per the service procedure to provide a new sealing surface.
Is this compatible with all 5.9L and 6.7L B-Series through 2018?
It fits many 1989–2018 B-Series applications referencing Cummins 3926126. Always confirm by ESN or parts catalog before ordering.
