Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. How Long Does a Crankshaft Seal Last?

How Long Does a Crankshaft Seal Last?

Crankshaft Seal

The crankshaft seal is located in the crankshaft of your vehicle. The crankshaft converts rotary into linear motion. This means it uses the force created by the pistons in the engine to move in a circular motion so the vehicle’s wheels can turn. The crankshaft is housed in the crankcase, which is the largest cavity in the engine block. For the crankshaft to work properly, it must be completely lubricated with oil so it is free of friction. There are two crankshaft seals, one in the front and one in the back, which are known as the front main and rear main seals respectively.

Since the crankshaft needs to be lubricated, there are seals on both ends of the crankshaft that keep the oil from escaping. In addition, the seals help to prevent debris and contaminants from entering the crankshaft itself. If this happens, the crankshaft may become damaged or stop working.

The crankshaft seals are made from durable materials so they can stand up to the harsh environment of the crankshaft. The materials they are made out of may include silicon or rubber. Although they are designed to handle the high pressure and temperatures, they can become worn and damaged over time.

The front seal on the crankshaft can be found behind the main pulley. If the seal starts leaking, the oil will get onto the pulley and oil will get thrown onto the belts, steering pump, alternator, and anything else that is close to the area. The rear seal is located along the transmission. The process to replace a rear crankshaft seal is complicated so it is best left to a professional mechanic.

Since the crankshaft seal can go bad over time, it is a good idea for you to know the symptoms before it completely fails.

Signs your crankshaft seal needs to be replaced include:

  • Engine oil leak or oil splattered on your engine
  • Oil spraying on the clutch
  • The clutch slipping because oil is spraying on the clutch
  • Oil leaking from the front crank pulley

The seal is an important part to keeping your crankshaft running smooth, and your crankshaft is necessary for your engine to run properly. Therefore, this repair should not be delayed.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

The Traveler’s Guide to Driving in Malaysia
CraigBurrows / Shutterstock.com Malaysia is a popular destination for many tourists today. The country has amazing sights and attractions that you will want to explore....
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
P0291OBD-II Trouble Code: Cylinder 11 Injector Circuit Low
P0291 code definition When your vehicle’s PCM registers the P0291 code, it means that a voltage reading came from the fuel injector circuit – for cylinder number 11’s fuel injector –...


Related questions

Q: Rear differential noise

The noise is not coming from the pinion seal, but the pinion bearings are bad and this is why the pinion seal is leaking. You will need to have the rear end bearings and seals replaced. If you'd like to...

Q: Gas leak

There are several lines and hoses that run underneath your vehicle that carry fuel. It is possible that due to the age of your vehicle that a line has rusted through or deteriorated enough to allow fuel to leak. I...

Q: Rear main seal leak.

The rear main seal is located in between engine and the transmission. Usually when seals start going out it's because of a pressure issue with the crank case. If the PCV or positive crankcase ventilation system gets clogged up, or...