Crankshaft Seal
The crankshaft seal keeps engine oil from leaking out where the crankshaft exits the engine. If you find oil drips under the front or rear of the engine, or notice your oil level dropping, a worn crankshaft seal is a likely culprit and should be replaced before the leak gets worse.
Find a TechnicianCommon causes
- Seal hardening and cracking from age and heat over many miles
- A worn or grooved crankshaft surface that no longer lets the seal grip
- High crankcase pressure from a clogged PCV system pushing oil past the seal
- Improper installation of a previous seal letting oil seep around it
- Oil contamination or sludge that degrades the seal material
Frequently asked questions
Can I keep driving with a leaking crankshaft seal?
A small leak is usually fine for a short while, but you'll need to watch your oil level closely. If oil runs low the engine can be damaged, so plan to have the seal replaced before the leak grows.
Why is a rear crankshaft seal more expensive to replace?
The rear seal sits between the engine and transmission, so reaching it often requires removing the transmission or flywheel. That extra labor makes it pricier than the more accessible front seal.
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