Can you drive with a rear main seal leak?
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 long does it take for rear seal Stop Leak to work?
Typically, you would start to see results after around 100-200 miles of driving, so if you are due to have the oil change in the near future, you would want to change the oil first. Otherwise, you are fine to add it to you existing oil. Thank you! Will the rear seal stop leak work on an older engine? 1974 Dodge 318Cid engine.
When to replace the rear main seal on a car?
When the rear main seal on your vehicle becomes worn or damaged, it can cause oil leaks. If you notice an oil leak coming from under the drivetrain of your vehicle, then you probably have a rear main seal leak and will need to replace it.
Is it OK to drive with a leaking rear main seal?
Driving with a rear main seal leak is dangerous due to the high possibility of a very fast leak. A fast leak will lower your engine oil level to dangerous levels very quickly, which can lead to permanent engine damage.
What damage can a leaking rear main seal cause?
If the seal tears or cracks at all your crankshaft rotation can cause the seal to get torn up very quickly causing a very fast leak. A fast leak can lower your engine oil level to dangerous levels very quickly and dangerously low oil levels can lead to permanent engine damage.
How much does it cost to fix a rear main seal leak?
It is designed to keep the oil where it should be and typically needs replacement when it shrunk or deteriorates. The rear main seal usually costs between $600-$900, with a service fee of around $550 to $820 out of the overall replacement charge.
What happens if you don't fix rear main seal?
What Happens if the Rear Main Seal Fails. Rear main seal leaks are so dangerous because it is possible for the leak to occur at a very fast rate. Due to the location, it is subject to high oil pressure. It is also connected to the engine, which must be slick with oil to function properly.
How do you slow down a rear main seal?
0:051:19How to Install BlueDevil Rear Main Sealer - YouTubeYouTubeStart of suggested clipEnd of suggested clipNow Blue Devil rear main seal er is guaranteed to restore dried shrunken. And crack seals to theirMoreNow Blue Devil rear main seal er is guaranteed to restore dried shrunken. And crack seals to their original condition. While you drive now it works in both gas. And diesel engines.
Is it worth replacing rear main seal?
Replacing a rear main seal can be so expensive the cost to replace it may be more than you have to spend, or even more than your vehicle is worth. When faced with a high dollar repair on an older vehicle it can be difficult to decide if it's worth dumping more money into an older vehicle that doesn't have much value.
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!
Does BlueDevil Rear Main Sealer really work?
Devil With a Blue Dress In days of old, shade tree mechanics poured lacquer thinner into the engine oil to puff up the rubber timing cover and rear main seals to stop leaks—and, yes, sometimes it worked.
How to tell if a rear main seal leak is serious?
If you’ve got a rear main seal leak you will have oil dripping off either your engine oil pan or the front of your transmission called the bell housing.
Where is the rear main seal located?
The rear main seal in your vehicle is at the back of the engine and seals the crankshaft as it exits the engine. Your vehicle’s flywheel or flexplate is then bolted onto the crankshaft flange ...
What is the difference between oil stop and rear main sealer?
Oil Stop Leak is more concentrat ed and is the universal application that will work for various leaks such as oil pan leaks, rear main leaks, valve cover gasket leaks, etc. Whereas the Rear Main Sealer is less concentrated and specifically formulated exclusively for leaking rear main seals.
What is an oil stop leak?
The Oil Stop Leak is a universal application and would treat a leaking oil pan gasket, valve cover seal, rear main seal, etc. where as the Rear Main Sealer is specifically formulated for the rear main seal. Feel free to contact our technical support line at 888-863-0426 with any other questions. Thank you! -BDP.
Why does my car smoke from the tailpipe?
If the smoke is coming from your tailpipe, it is an indication that you’ve got a bigger problem like too much oil or internal damage to your engine. If the smoke is coming from your engine bay, it is an indication that you have a bigger leak and should consider replacing the seal or gasket to avoid a fire hazard.
Can a rear main seal leak?
Bad. A rear main seal leak can cause some big problems in your vehicle. To make things worse, replacing a rear main seal can be one of the most expensive jobs you can do on your car next to replacing the head gaskets or rebuilding your transmission.
Is it dangerous to drive with a rear main seal leak?
The speed of the leak. The possibility of a very fast leak is the biggest factor that makes it so dangerous to drive with a rear main seal leak. As we just mentioned, your rear main seal is in a place that gets a lot of oil thrown at it and has the added wear of the crankshaft spinning inside of it. If the seal tears or cracks at all your ...
Why is my rear main seal failing?
The primary cause of the rear main seal failure is rupture inside the engine or on a component connected to the engine. For many car owners, such news could cause a bad day because the rear main seal replacement is one of the expensive, most labor-intensive, and most-dreaded repair jobs to do on your vehicle.
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.
What happens if your crankshaft is worn out?
Worn main bearing: If your engine main bearing is bad or worn out, the crankshaft will dangle inside the bearing leading to stretching and moving the rear crankshaft seal while the engine is running.
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 condition of a crankshaft?
Crankshaft condition: The rear crankshaft seal lip rides directly on the crankshaft. Therefore, the crankshaft surface that the inner seal drives on is critical. Any wear or imperfections on the crankshaft can result in a leak. The surface can be restored by installing a sleeve kit on it.
What causes oil to smoke under car?
Smoke from under the vehicle: A leaking rear crankshaft seal will often drip on the exhaust and cause smoke from under the car.
What to do if your rear main seal is leaking?
Luckily, if your rear main seal is leaking, you have a few options outside of replacing your engine or paying for costly maintenance. Stop leak products are relatively new to the automotive market and have made great strides with recent formulas.
What is the difference between a rear main sealer and an oil stop leak?
Whereas the Rear Main Sealer is specifically formulated for the rear main seal.
Why is the rear main seal important?
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. Luckily, fixing the seal is extremely easy ...
How much does it cost to replace a rear main seal?
The actual seal that is broken is often a relatively low-cost part, often under $50 dollars but sometimes as low as $15.
What happens if you fix a rear main seal?
A rear main seal that requires fixing will leave oil stains under a parked vehicle. Your vehicle may also demonstrate a dramatic loss of oil in a short period of time.
Is it bad to put oil in your exhaust pipe?
Spreading oil over your hot exhaust pipe is, most importantly, a fire hazard! It can also but also lead to unpleasant smells and plumes of smoke coming from your engine. Just letting a rear main seal leak go is a poor option, even if you don’t intend on keeping your car for very long.
Why is my rear main seal leaking?
A rear main seal leak is among the worst things that can happen to any vehicle because the rear main seal is very hard to reach and it requires much of your engine to be disassembled. On most modern engines, the seal’s failure is due to a condition inside the engine or a component connected to the back of the engine, ...
How much does it cost to replace a rear main seal?
It can easily cost you from $800 to $1,200 at a mechanic.
How to tell if your engine has worn bearings?
If your vehicle has worn main bearings, the crankshaft is able to move excessively inside the bearings which will stretch and move the rear main seal while the engine is running. This will allow oil to leak past the seal. It is difficult to tell if your engine has worn main bearings without removing a lot of components.
Why is my crankshaft leaking oil?
If the seal tears or cracks even only slightly, the crankshaft rotation can cause the seal to get torn up very quickly causing a fast leak.
What is the purpose of the rear main seal?
The rear main seal allows the crankshaft to exit the engine case so it can bolt to the flywheel or flex plate and transfer its energy into the transmission. The rear main seal also holds the engine oil back and keeps it inside your engine where it can keep your main bearings lubricated.
What is a split seal?
Made of rubbery material, the split seal has a lip-shape and is fitted in one direction to prevent the passage of oil. Though effective regarding this purpose, neoprene seals are equally vulnerable to leaks as rope/wick seals.
Where does oil come from on a car?
On most engines, oil leaks can occur above and below the rear main seal. It could be a leaking oil pressure sensor, oil pan gasket or galley plug near the seal that causes oil to come from the bell housing. Adding dye to the oil can help reveal where the oil is actually coming from.
How to tell if oil leaks on transmission?
As we mentioned, higher oil leaks can still leave traces of oil around the back of your engine. One of the best ways to prove that your oil leak is actually a rear main seal leak is to check for oil on the engine side of your flywheel or flexplate. Most transmissions will have an inspection cover on the bell housing that you can remove to peek in and check things out. Open that cover and grab a flashlight and see if you can find evidence of a rear main seal leak. If it’s dry inside the transmission bell housing, you probably have a leak elsewhere.
Why does my oil drip from the back of my oil pan?
Engine Oil Dripping from the Back of Your Oil Pan. Like having oil on your bell housing, the back of your oil pan can get oil if you’ve got a rear main seal leak. Make sure to check again for other indications of a rear main seal leak as oil can drip here if your oil pan drain bolt is loose, or if you’ve got an oil pan gasket leak.