
Before replacing the rear main seal, you will need to take the driveshaft off. After that, you will need to find the flexplate. It is a round metal disc with many holes on it. Use a wrench and a screwdriver to help you with removing the flexplate. By doing this, you are able to reach the rear main seal easily.
How much does it cost to repair rear main seal?
The rear main seal for a car can cost less than $50, so you might be wondering why it costs hundreds to replace the rear main seal. The main portion of the cost that you will be charged at a mechanic’s auto body shape is due to the substantial amount of labor that it takes to replace the seal, and potentially the gaskets, seals, and other ...
How much time to replace rear main seal?
The rear main seal usually costs between $600-$900, with a service fee of around $550 to $820 out of the overall replacement charge. How long does it to replace a rear main seal? Replacing a rear crankshaft seal requires long hours and effort.
How to tell if your rear main seal is leaking?
Signs & Symptoms of Rear Main Seal Leaking
- Oil Spots. The most common sign of a leaking rear main seal is oil spots on a driveway or garage floor where the vehicle is parked for long periods of ...
- Smoke. Often leaking oil from a rear main seal will drip onto the vehicle's exhaust and cause smoke to come from under the car.
- Accumulation of Debris. ...
How long can I ignore a leaky rear main seal?
It is no news that engine seals deteriorate over a long period of use due to oil acidity, heat, and several other related issues, usually due to lack of maintenance. In such a case, the rear main seal stop leak is needed to recondition the seal and work for a few thousand miles. To recondition the rear main seal, get a blue devil rear main sealer.

Can you replace a rear main seal without removing the engine?
You can cautiously poke at the crankshaft to remove the seal. This seal is the rear main seal you need to take off. Remove it and install the new one. This is the procedure on how to replace a rear main seal without removing transmission easily in no time.
How do you fix a rear main seal leak?
0:288:45HOW TO FIX A REAR MAIN SEAL LEAK - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd there's a gasket behind this cover plate some cars will use a gasket itself behind the coverMoreAnd there's a gasket behind this cover plate some cars will use a gasket itself behind the cover plate. And other times they just use silicone.
Can you seal a rear main seal leak?
If you've discovered a rear main seal leak in your vehicle, seal the leak today before it's too late. Head to your local auto parts stores and pick up BlueDevil Rear Main Sealer. Simply add BlueDevil Rear Main Sealer to your vehicle's engine oil and your rear main seal leak will be stopped as your drive your vehicle.
What is the best product to stop a rear main seal leak?
Top 10 Picks Best Rear Main Seal Leak Additive For 2022#Product1Bar's Leaks Rear Main Seal Repair, 16.9 ozBuy on Amazon2Bar's Leaks MS-1 Main Seal Motor Oil Leak Repair, 32 fl. Oz.Buy on Amazon3BlueDevil Rear Main SealerBuy on Amazon4Bar's Leaks Oil Seal Engine Oil Burning and Leak RepairBuy on Amazon6 more rows
Is it worth fixing rear main seal?
The rear main seal is one of the essential seals in your vehicle that you don't expect to leak unless you're dropping your engine or transmission because replacing this seal requires dissembling the engine or transmission before you can reach it.
How hard is it to change a rear main seal?
Its' Hard. Replacing a rear main seal is time consuming, requires special knowledge of your vehicle and the use of special tools if you are going to do it correctly and without placing you or your vehicle in danger.
Does Blue Devil work rear main seal?
BlueDevil Rear Main Sealer permanently stops rear main seal leaks. Just add to the engine oil to restore and seal gaskets. BlueDevil Rear Main Sealer is a great repair for timing cover leaks.
What causes a rear main seal to go out?
Excessive heat, old age, high mileage, infrequent use, and worn bearings can also be factors contributing to rear main seal failure.
How many hours does it take to replace a rear main seal?
Replacing a Rear Main Seal However, the process to get to the rear main seal to replace it often requires removal of the entire engine and transmission from the vehicle, a job that can only be done by very skilled mechanics and even then can take 6-10 hours!
Will Stop leak harm my engine?
When you carefully follow the instructions for our engine, radiator or other stop leak products, there is no risk of damage.
Is Blue Devil safe to use?
BlueDevil contains no solid or particulate matter, and will not clog or harm your engine. It bonds to metal, aluminum, cast, alloy, or plastic, and it's safe and easy to use.
Do oil leak sealers work?
The short answer is . . . sort of. While the new formulas will stop those leaks in many situations, they aren't a permanent solution. The leaking seal will, sooner or later, need replacing.
How to replace a rear main seal?
By removing all the additional parts, you are almost done with the process of how to replace a rear main seal without removing the transmission. Generally, the rear main seal is pressed into the hood through bolts into the engine block. Here in the middle, you can see the crankshaft that comes into action when the engine is running. At the center of the crankshaft, there is a tiny piece, which is a pilot bearer. The seal hood normally has six to ten mm bolts that you must take off. After removing the entire set of bolts, remove the hood of the seal. Be careful while removing the housing of the seal as it is made with fragile material of aluminum that is prone to cracks and dents.
What is required for a rear main seal replacement?
1. The Job Complexity. Rear main seal replacement requires a certain knowledge of engine construction as well as how it is attached to the transmission. There are different ways of installing the rear main seal as well as the transmission, so car shops have to charge a little more as each rear main seal will be a little different.
What Is A Rear Main Seal?
If you want to know how to replace rear main seal, you will need to know what it actually is. Just like its name, the rear main seal is installed at the rear of your car’s engine. Its main job is to help the crankshaft. It prevents the oil from leaking into the crankshaft. Therefore, the crankshaft can finish its work and let the engine coordinate well. If the rear main seal is malfunctioned, the oil will leak fast. Then the oil will dry up and stay there will stains, destroy the system.
What Makes a Rear Main Seal to Be Ruined?
First, it could be the malfunction of the crankshaft. When it leads to breakage of the crankshaft, the rear main seal will be affected. Second, the rear main seal can get into trouble because of bad installation from the producer or the mechanic. Also, the weather conditions and the temperature condition inside the car can affect the seal. Because of dust and debris, plus the hot or cold weather, the rear main seal may face with the threat of shortening its lifespan.
How many bolts does a crankshaft seal have?
At the center of the crankshaft, there is a tiny piece, which is a pilot bearer. The seal hood normally has six to ten mm bolts that you have to take off. After removing the entire set of bolts, remove the hood of the seal. Be careful while removing the housing of the seal as it is made with fragile material of aluminum ...
What is the last layer of the rear main seal?
The flex plate is the last layer that covers rear main seal replacement. By removing the flex plates you will be able to unbolt the seal from the rear end. 3. Remove the Rear Main Seal Hood. Now that you have taken away all the supplementary parts, it is time to remove the rear main seal.
Where is the rear main seal located?
The seal is mounted on a plate, which is located at the rear of the engine. Consistant car vibration and heat result in the failure of rear main seal. In this situation, it is better to replace the seal.
How to fix a leaky rear main seal?
To recondition the rear main seal, get a blue devil rear main sealer. This product is specially formulated to stop the rear main seal leak. It does this by restoring rubber gaskets and seals, it is also an excellent repair for timing cover leaks, and it’s safe to be used for both gas and diesel engines. It’s also compatible with both synthetic or conventional oils. Keep in mind that this will not work if you have a chunk, tear, or hole on the seal. No product can repair a big chunk or hole on a rubber seal. So, if you have a giant hole on the rear crankshaft seal, follow the below steps to fix it.
What is a rear main seal?
What is a rear main seal, and how does it work? The rear main seal is found at the back of the engine between the engine and the transmission, which seals the crankshaft’s back end from leaking. It is an expensive fix because, most times, it requires removing the transmission or dismantling the engine.
How to remove the main seal on a flexplate?
Remove the rear main seal bolts: After removing the transmission, the clutch, and the flexplate, the next thing is to remove the rear main seal. You may see crankcase bolts that link the crankcase to the rear crankshaft seal housing, break free and take off these bolts. The rear crankshaft seal housing has some 10mm or 12mm bolts holding it on the back of the engine block. Take off these bolts and remove the seal housing. The housing might prove stubborn to come off; use a Flathead screwdriver to pry it off.
How to tell if crankshaft seal is leaking?
Just like every other mechanical component, some signs and symptoms will pop up to notify the driver of a defective or leaking rear crankshaft seal. Oil puddles: The most common sign of a rear crankshaft seal is oil puddles on the garage floor or the driveway.
Why does my crankshaft leak?
Engine oil condition: One of the factors that can cause the rear crankshaft seal to leak is using the wrong type of engine oil or low oil level. Most engine oils have chemical additives that might affect the seals in the engine. An irregular oil change will deteriorate the seals.
Why does my engine seal deteriorate?
It is no news that engine seals deteriorate over a long period of use due to oil acidity, heat, and several other related issues, usually due to lack of maintenance . In such a case, the rear main seal stop leak is needed to recondition the seal and work for a few thousand miles.
What is the seal on a crankshaft?
The rear crankshaft seal is usually made of silicone or rubber. The seal wears out over time as a result of corrosion from road salt, crankshaft rotational forces, and other environmental factors. Driving with a rear main seal leak can be very dangerous and can lead to total engine failure.
How much does it cost to fix a rear main seal?
The average cost to repair a rear main seal is anywhere from $659-$831, depending on where you live and the shop that does the work.
What is the main seal on a car?
The rear main seal is what seals the crankshaft to the engine block and keeps engine oil from leaking out around the crank. It’s called the rear main seal because it seals the rear of the crank shaft where it bolts to the transmission. In order to properly complete this job a garage would have to have a transmission jack, engine hoist and engine stand. Many garages do not have this equipment on hand, and the ones that do often charge a premium for them.
What oil stop leaks on a C1500?
Thank you for asking about your Chevy C1500. Based on your description, we recommend using the BlueDevil Oil Stop Leak http://store.gobdp.com/oil-stop-leak-49499/. The Oil Stop Leak is a universal application, so it would treat leaking oil pan gaskets, valve cover seals, rear main seals, etc. You should expect to see results after about 100-200 miles of driving.
What is the seal on a car that keeps oil from leaking?
Often with a rear main seal leak the engine has to be removed from the vehicle to replace the seal. The rear main seal is what seals the crankshaft to the engine block and keeps engine oil from leaking out around the crank. It’s called the rear main seal ...
Can a rear main seal leak?
Yes, it can be the rear main seal leaking transmission fluid. We do manufacture the BlueDevil Transmission Sealer but based on your description of the leak it may be too large for what BlueDevil is intended to fix. The only solution may be to have the seal replaced.
Can a rear main seal leak trans fluid?
No the rear main seal can not leak trans fluid. That would be the front seal on the trans
Does Chevy Trailblazer have transmission oil leak?
Thank you for asking about your Chevy Trailblazer. It is very unlikely that engine oil leaked into your transmission fluid. Please contact our technical support line at 888-863-0426 so that we can get a little better understanding of the vehicle’s condition and be able to make any appropriate recommendations.
What Is Done During A Rear Main Seal Replacement?
To determine where the oil leak is coming from in your car, the mechanic will have to place a dye into the oil. This oil shows up under the UV light to see where the rear main seal leak is coming from. Once the issue is diagnosed, the mechanic can then determine where the leak is originating from to estimate the rear main seal replacement cost.
What Is A Rear Main Seal?
The rear main seal within your car has the job of keeping the oil inside of the rear of the engine. This is where the crankshaft connects with the transmission. The crankshaft converts linear energy into rotational energy, letting the car drive forward.
What If I Don’t Have Money For The Replacement But I Can’t Do It Myself?
If you don’t know how to perform the above steps to replace the rear main seal , you might not want to pay for the amount of money in an expensive rear main seal replacement cost. In this case, bringing your car to a reputable location to obtain a fair quote is your best bet. Check out CashCarsBuyer to sell your junk car and earn some extra money to put towards a new and safe vehicle!
How to remove seal housing?
The seal housing will have bolts holding the housing to the rear of the engine block. Remove these bolts by turning them counterclockwise. Now, you can remove the entire seal housing. Use a large screwdriver to pry the housing off of the engine block.
How to remove rear crankshaft seal?
Remove The Rear Main Crankshaft Seal. Sometimes, the rear main crankshaft seal can get stuck. You need to remove the seal using a gentle prying technique . Now, remove the rear main seal by hand from the hub.
What happens when you replace the main seal on your car?
When you replace a rear main seal, there might be other components of your vehicle that require replacing. For example, the oil pan generally needed to be removed. The oil pan removal requires the mechanic to install a new gasket. A degraded gasket is the most common cause of oil leaks. Additionally, you might choose to replace your front crank seal or the clutch, saving you labor costs in the future since your mechanic is already there and has done the hard work.
What is the main seal on a transmission?
The anatomy of the rear main seal consists of a cylindrical metal piece in the middle of the seal – this is the crankshaft. The smaller piece in the center of the crankshaft is a pilot bearing, included on only rear-wheel-drive manual cars.
Why do engine seals crack?
Very often, engine seals become dry and crack, due to heat, oil acidity, and a host of other maintenance related results (usually from a lack of maintenance!) that can be reconditioned without having to be replaced. Now this is within reason… you’re not going to be able to drive a car 500k miles and expect this stuff to never fail!
Why is my car's seal shrunken?
Sure there’s always a chance it won’t work, but you’re not out thousands of dollars, and you might get lucky and just have shrunken seals due to someone not changing the oil frequently enough, which causes the engine oil to get acidic and affect the rubber. Very often simply reconditioning them can bring them back to life for a short period of time, and they will perform just fine for 10’s of thousands of more miles. (or at least give you options to prepare for your repair)
How long does it take to put a car on a lift?
Most cars have too many other components int he way, and require being put on a lift for around 8 hours of shop labor. Some makes and models have to have the transmission dropped in order to remove everything and access the block in good shape, which is extremely labor intensive compared to something like a valve cover job up top.
Is oil leak stopper a scam?
This is why some people have great success with some stop leak products, and others say it’s a scam and doesn’t work.
Can a tear in a gasket plug a gaping hole?
Like I mentioned above, if you car or truck has a tear in the gasket, or there is actually seal material missing, no amount of leak stop is going to plug a gaping hole. You need to have a mechanic replace the seals, since any type of jerry-rigging is only going to last you so long.
Can oil leak sealer repair a leaking gasket?
Oil Leak Sealer Can’t Repair A Torn Or Worn Gasket. The way stop oil leak products work, depends on the brand you buy. There are some out there that claim to thicken the oil viscosity enough to stop the oil from getting by weak seals.
Are Oil Stop Leak Products A Scam Or Do They Really Work?
If you’ve looked around a bit already, or checked some of the Amazon reviews, I’m sure you can see the huge difference in feedback.
