Help keep engine oil where it belongs with the FEL-PRO engine crankshaft seal kit, part number BS40678, a premium rear crankshaft seal made for the real-world repair environment. It fits many vehicles, among them the 2002-2009 Chevrolet Trailblazer, 2002-2009 GMC Envoy and 2002-2006 Chevrolet Trailblazer EXT with the L6-4.2L engine, and is a direct-fit replacement for the listed applications.
Installed at the rear of the crankshaft, this seal helps retain engine oil inside the engine. The seal body stays stationary while its lip rides on the rotating crankshaft. FEL-PRO designs its gaskets and seals specifically for repair work, using proprietary materials intended to give a reliable seal even on troublesome applications and imperfect sealing surfaces.
- Application-specific design: engineered for a precise fit on the listed applications and validated for fit, form, and function.
- PTFE rubber, one-piece: FEL-PRO lists the seal material as PTFE rubber, in a one-piece design.
- OE-level quality: FEL-PRO states that it meets or exceeds all original equipment specifications and that it is engineered and manufactured specifically for repair applications.
- Premium grade: part of FEL-PRO's Premium grade, with a country of origin of Taiwan.
If oil is seeping from the rear of the engine where it meets the transmission, a worn rear crankshaft seal may be the cause. Confirm the leak source before replacing. The listed applications use one kit. See the "Vehicles it fits" section for the full list of fitting vehicles.
Interchange: 12581717 · 24577096 · JV1668 · RS30235 · 191008501
Product information is for general reference and may contain errors. See our Disclaimer.
This part cross-references / interchanges with the following part numbers:
12581717, 24577096, JV1668, RS30235, 191008501
Frequently Asked Questions
What does the FEL-PRO crankshaft seal kit do?
It seals the rear of the crankshaft and helps keep engine oil inside the engine. The seal body stays stationary while its lip rides on the rotating crankshaft.
Will it fit my 2002-2009 Chevrolet Trailblazer?
Yes. It is a direct-fit replacement for the 2002-2009 Chevrolet Trailblazer with the L6-4.2L engine. Check the "Vehicles it fits" section for every other vehicle it fits.
What is the seal made of?
FEL-PRO lists the material as PTFE rubber, in a one-piece design. It is a Premium-grade part and its country of origin is Taiwan.
What are signs a rear crankshaft seal may need replacing?
Common signs include oil seeping at the rear of the engine near the transmission and oil drips under the vehicle. Other seals and gaskets can leak too, so confirm the source before replacing.
How many kits do I need?
The listed applications use one kit, and this listing is for one kit.
