Symptoms of a Bad or Failing Crankshaft Seal

The crankshaft seal is the seal located on the front of the engine that seals the end of the crankshaft with the timing cover. Most crankshaft seals are made of rubber and metal and are round in shape. They are usually installed in the front timing cover and seal the end of the crankshaft as it rotates. While they are a relatively simple component, they serve an important purpose in keeping the oil that is constantly being used and tossed by the crankshaft as it rotates from leaking out of the engine’s crankcase. When they fail they can cause leaks which can make a mess, and if left unattended, can put the engine at risk of serious damage. Usually a crankshaft seal will display a few symptoms that can alert the driver that there may be an issue that should be serviced.

High mileage

If your vehicle is approaching high mileage, perhaps upwards of one hundred thousand miles, then the crankshaft seal may be approaching the end of it’s recommended service life. All manufacturers have a recommended service interval for most of the components on a vehicle. Servicing the crankshaft seal according to the recommended service interval can prevent the seal from failing in the first place, which can cause other problems.

Oil leaks

Oil leaks are the most common symptom of a problem with the crankshaft seal. If the crankshaft seal dries out, cracks, or breaks, it can cause an oil leak. Small leaks can cause oil to accumulate on the undersides of the engine, while larger ones may produce a drip of oil from the front of the engine.

The crankshaft seal is mounted behind the engine’s main crankshaft pulley, so servicing it requires the removal of the belts and crankshaft pulley and harmonic balancer before it can be accessed. For this reason, if you suspect your crankshaft seal may be leaking or near the end of its service life, have the vehicle inspected by a professional technician, such as one from YourMechanic. They will be able to look over your car and determine if it needs a crankshaft seal replacement.


Next Step

Schedule Vehicle Engine Mechanical Inspection

The most popular service booked by readers of this article is Vehicle Engine Mechanical Inspection. Once the problem has been diagnosed, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. YourMechanic’s technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. We currently cover over 2,000 cities and have 100k+ 5-star reviews... LEARN MORE

SEE PRICING & SCHEDULING

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

Recent Vehicle Engine Mechanical Inspection reviews

Excellent Rating

(4)

Rating Summary
4
0
0
0
0
4
0
0
0
0

Jeremy

21 years of experience
802 reviews
Jeremy
21 years of experience
Kia Soul L4-1.6L - Vehicle Engine Mechanical - West Palm Beach, Florida
Highly experienced Able to provide every relevant answer for the case. Highly recommended Thank you Jeremy
Mercedes-Benz S550 - Car is not starting Inspection - Boynton Beach, Florida
Very knowledgeable & friendly.

Raymond

38 years of experience
613 reviews
Raymond
38 years of experience
Cadillac Brougham V8-5.7L - Vehicle Engine Mechanical - Las Vegas, Nevada
Talent and passion for what you do in any field is critical, Raymond seems to have both. I have dealt with many Mechanics in my day Raymond is one of the best. Thank you sir.
Lexus RX330 - Alternator - Las Vegas, Nevada
RAY is a very experienced mechanic and am always satisfied with his work. I would definitely recommend him to my friends who would need their car serviced.

Ronald

42 years of experience
519 reviews
Ronald
42 years of experience
Ford Mustang V8-5.0L - Vehicle Engine Mechanical Inspection - Houston, Texas
Great personality and very friendly and helpful.

Rusty

24 years of experience
567 reviews
Rusty
24 years of experience
GMC Sonoma L4-2.2L - Vehicle Engine Mechanical Inspection - Arlington, Texas
Great overall impressions. Vechile is driveable and runs terrific now.

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

Related articles

How Long Does an Axle Shaft Seal Last?
The The axle shaft seal in your car is a gasket that keeps fluid from leaking out of the vehicle’s differential. The differential itself is what sends power from the engine of your car to its transmission, and finally to...
How Long Does a Clutch Slave Cylinder Last?
The The clutch slave cylinder is located on the inside or outside of the transmission. If the slave cylinder is mounted on the outside of the transmission, it is normally attached by two bolts. Every time hydraulic pressure is applied,...
How Long Does a Cold Air Intake Last?
The The cold air intake’s purpose is to help bring cool air into the vehicle’s engine. It does not come standard on modern vehicles. Instead, it is an aftermarket part that can be added once you purchase the car. If...

Related questions

The car won't go into gear while running, makes a grinding sound
The clutch may not be disengaging. This would need to be checked by having the car in gear and clutch in then start the car to see if the car wants to move forward. Do this test when you are...
Car is overheating, usually when it's hot and the engine idles.
You most likely have a transmission cooler that is leaking (https://www.yourmechanic.com/services/transmission-fluid-is-leaking-inspection) into the coolant inside the radiator. The transmission cooler is built inside the side tank of the radiator, and if it blew out, then you will have transmission fluid...
Clutch will not engage and has no pressure. What is the worst case scenario and estimated cost for repairs at a dealer?
Hi there. From the description you have provided, your clutch will not engage, has no pressure, cannot engage any forward or reverse gears, is difficult to estimate the cost of repair at a dealer. Diagnosing the inoperative clutch, would help...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (844) 997-3624 · hi@yourmechanic.com