Interstate-McBee M-5259499 Rear Oil Seal – 1989–2018 5.9L/6.7L Cummins (Aftermarket)

Stop bellhousing oil leaks with this OEM-style rear crankshaft main oil seal from Interstate-McBee. The M-5259499 is a direct-fit aftermarket replacement for Cummins applications in 1989–2018 Dodge/Ram 2500/3500 trucks equipped with 5.9L or 6.7L Cummins engines.

• Direct-fit replacement: Matches OE dimensions for reliable sealing at the rear main.
• For good crank surfaces: Non-sleeved design intended for non-damaged crank flanges.
• Installer ring: Supplied with a cardboard inner ring for installation alignment.
• Aftermarket value: Interstate-McBee quality at an aggressive price point.

Specifications

Vehicle Fitment

Always verify by VIN/ESN and crank surface condition.

• Dodge/Ram 2500 & 3500 – 5.9L Cummins (1989–2007)
• Ram 2500 & 3500 – 6.7L Cummins (2007.5–2018)

What’s Included

• (1) Rear main (rear oil) seal – M-5259499
• Note: Cover gasket, installation tool, and repair sleeve are not included.

Recommended Add-Ons

• Rear main cover gasket (’89–’02): Cummins 4947667
• Rear main cover gasket (’03–’18): Cummins 5443388
• Installer tool: CTA 3880 (or equivalent)

Install Tips

• Inspect crank flange for grooves; if worn, use a repair-sleeve style seal instead.
• Set to the proper depth using an appropriate installer; do not drive flush unless specified by OE procedure.
• Degrease mating surfaces and verify no leaks from cam plug or rear cover gasket before reassembly.

Why Buy From CPP Diesel

• ESN-verified fitment support from real diesel techs
• Fast shipping & easy returns
• Curated Cummins parts with cross-links to the gaskets, tools, and hardware you’ll actually need

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