Cost estimate for rear main seal replacement

Estimated cost to replace rear main seal.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Billing question for to replace the rear main seal (rear crankshaft seal) on a 2003 Lexus GS300 with a L6-3.0L engine.

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Some estimates put the cost at around $350-$450 for labor alone. However, this cost can vary depending on the make and model of your vehicle, as well as your location and the specific shop you take it to.
Fortunately, the front crankshaft seal is easier to replace than the rear seal, with replacement costs starting around $200 and reaching $500 and above, depending on your vehicle and engine layout.
The cost of fixing a rear main seal leak can vary depending on the make and model of your vehicle and where you take it. The actual seal that is broken is often a relatively low-cost part, often under $50 dollars but sometimes as low as $151. However, the repair is expensive.
It`s a very important seal since it is so low on the engine a significant amount of oil can quickly leak from it, allowing your engine oil levels to get dangerously low before you have time to add more oil. That`s why, if yours is faulty, a rear main seal leak fix should be at the top of your to-do list.
The complexity of the job

Since many vehicle manufacturers have different ways of installing the rear main seal as well as the transmission, independent shops have to charge a little more for the job as each rear main seal will be a little different.

A rear main seal, or crankshaft seal as it is commonly referred to, is a big, round rubber seal between the engine and transmission. The rear seal fits snuggly around the rear of the crankshaft and keeps the engine oil from escaping.
What Happens When the Rear Main Seal Fails? Failure of the rear main seal usually results in an oil leak from the camshaft into the transmission bell housing. While the seal generally doesn`t cause any major or catastrophic engine problems, the oil leak it causes can potentially lead to more serious issues.
To prevent future leaks and for outstanding preventive maintenance, install Rear Main Seal Repair every 5,000 miles or with every oil change.
The traditional fix for a leaking main seal is to replace it, but because of the typically high labor cost some vehicle owners use oil additives designed to restore seals. In some cases, that can stop or slow leaks. Other drivers may switch to a heavier oil, such as 10W30 instead of 5W20.
Fel-Pro recommends removal of the engine and crankshaft for a rope seal installation to ensure a reliable seal. There are tools available to try to pull a rope seal into the block with the crank still in place. However this can be very difficult and may damage the rope material while trying this method.
Since rear main seal leaks are uncommon on most vehicles it`s very possible that you`ve got another leak higher up on the motor that is dripping down and just looks like a rear main seal leak.
This repair takes on average 1.96h – 2.40h for a mechanic to complete. Your crankshaft seal keeps oil and other debris from spreading through the undercarriage of your car as you drive.
Excessive heat, old age, high mileage, infrequent use, and worn bearings can also be factors contributing to rear main seal failure.
Seal lips should be generously lubricated to where they are wet during start-up, especially if an engine, transmission, or rear axle is going to sit for a while before operation. Dry seals and spinning shafts don`t mix. A dry seal will tear and then leak.
If this critical seal is damaged or weakened, oil leakage can cause serious powertrain problems that could affect both the transmission and the engine itself.
What should I do? A: Overfilling an engine with oil can put additional pressure on seals and, over time, can cause an oil leak.
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.
Oil leaks are often the most common symptom a car owner will notice when the seal starts to fail. When the crankshaft seal dries out, breaks, or cracks, there is room for oil to leak out. Even a small leak is enough for oil to accumulate on the engine. The larger leaks can make the oil drop to the front of the engine.
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Crankshafts seals do not last forever. If you are nearing 100,000 miles, then your crankshaft seal is near the end of its recommended service life. Manufacturers have a service interval that they recommend for most vehicle parts.

Under ideal conditions, they`d last indefinitely. However, they`re usually made of copper and lead compounds, which are subject to a variety of weaknesses.
Is Blue Devil Bad for Your Engine? The answer is a resounding no. And if you are wondering about the safety of using other brands of rear main seal conditioners and stop-leak products like Bar`s Leak or Justice Brothers, don`t worry. They almost all use the same active ingredient.
The rear main seal— rear crankshaft seal or RMS—is the working seal against the rotating crankshaft where it exits the rear of the engine and connects with the transmission. The rear main seal is used to prevent oil loss from the rear of an engine.
The experienced Field Service Engineers at Lycoming indicate that a leaking crankshaft oil seal is frequently caused by a restricted breather or an oil-slinger clearance that is too tight. The leak might also be caused by a propeller defect which places an abnormal side load on the crankshaft oil seal.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

How much to replace rear main seal or will BlueDevil rear main sealer work?
ANSWER : Hi there. Former Toyota/Lexus master technician here. I can tell you from experience that using any kind of sealer is a literal "Band-Aid" that will not last and could damage internal engine components if some of it breaks loose into the crank case. Your Mechanic does not provide rear main oil seal service at this time, but I would definitely recommend pursuing a qualified technician that can perform the service properly with a quality seal. I suggest using a factory seal as this is a repair that no one want to do twice; the second time either party’s expense. Your Mechanic is here for many of your other service, diagnostic, and repair needs 7 days a week. Feel free to schedule your next service at

What is an estimated cost to replace the rear main seal?
ANSWER : Hi there. The rear crankshaft seal is placed along with the transmission; therefore, the process of replacing it requires the removal of transmission, as well as the clutch and flywheel assembly. This is a very involved job that should be completed at a professional automotive shop; which is why our mobile mechanics are not able to complete this task. As such, we’re not able to provide you with a quote for this service. Good luck and thanks for contacting

Rear Axle Seal Replacement – What type seal?
ANSWER : Hi there, thanks for writing in. I recommend buy the Toyota OEM part. Although we could go into high detail as to the precise technical differences amongst the various and competing aftermarket seals you are describing, such will not change the conclusion at all. Generally speaking, aftermarket parts are NOT as good as the factory OEM parts. Large car manufacturers spend hundreds of millions of dollars, indeed billions, developing the technologies used in these vehicles and ALL of the parts are extraordinarily carefully engineered to fit very precisely and perform specific functions. In the aftermarket, they try to duplicate that, but more often than not, it does not work. Toyota OEM quality in particular is not duplicated well, if not at all, in the aftermarket.

Cost estimate for rear main seal replacement
ANSWER : Billing question for to replace the rear main seal (rear crankshaft seal) on a 2003 Lexus GS300 with a L6-3.0L engine.

aloha! i was told it would cost me $1870 to get a rear axle replacement. i have a 2006 toyota sequoia with mileage of 80,000. it
ANSWER : Aloha. Ah – the infamous "it’s all gone" excuse. To be quite blunt, you’re being ripped off. If a professional mechanic can’t explain what exactly is damaged with any mechanical component, they are taking advantage of you. I would get your car back and contact a different mechanic. Or, feel free to send us some information about the symptoms your car is experiencing that led you to take the car to the mechanic in the first place. Maybe we can help diagnose your issue and allow you to bring that info to a different mechanic. Mahalo.

How much is it to replace the rear main seal on a 2007 Hummer H3
ANSWER : Hello. It is common for the rear main seal to leak on this engine. Over time the seal fails and this occurs. You will need to take this to a shop that can remove the transmission to change the seal out.

Spongy brakes after replacing rear discs, pads and refurbing rear calipers. Bled so many times to no avail!
ANSWER : All four wheels have to be bled starting with the right rear, then left rear, right front, and left front. Inasmuch as air may be trapped as much as 10 feet from the bleeder screw, you have to have a relatively fast, and substantial (in volume) flow of brake fluid during bleeding to expel all air from the system. Generally, 5 to 10 PSI on a pressure system is sufficient. 20 PSI is not necessary. You should use a power bleeder, they are not very expensive for a simple one. If you car is equipped with ABS and/or electronic stability control, you will need a VAG 1551, VAG 1552, or equivalent bi-directional scan tool that is capable of activating the ABS/ESC pump. Activation is necessary to expel air from the ABS components of the system. If you would like to have this checked, a qualified professional from YourMechanic can come to your location to inspect the spongy brake issue and let you know what needs repair.

I am having transmission issues in my 2006 Chevrolet Avalanche after replacing the rear main seal.
ANSWER : Hello. It sounds like the pins in the transmission female connector may have gotten bent when you pressed the connection back in. From the codes you are getting you are having connection issues. It is hard to see it but you will need to check the pins. If any are damaged then the wiring harness internal to the transmission will need to be replaced. You may need to get some assistance from a transmission specialist with this.