Why does my car still leak oil after replacing the seal?
Persistent oil leaks after a part replacement are often caused by improper sealing in critical corners or underlying installation errors that basic gasket replacements fail to address. This leaves vehicle owners trapped in a repetitive cycle of fixing the same leak without finding a permanent solution.
What the numbers show
Counted from the threads quoted below. How we count
- This comes up 10.2× more often in r/MechanicAdvice than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Taking the car to a different shop for inspectionDid this help you?
- 2Cleaning the area to locate the exact source of the leakDid this help you?
- 3Filing down high spots on the mating surfaces and replacing the housing and seal againDid this help you?
- 4Waiting the full 24 hours before turning on the engineDid this help you?
- 5Visually inspecting the area for leaks after driving ~500 milesDid this help you?
- 6Taking the vehicle back to the dealership for diagnosis and component replacementDid this help you?
- 7Emailing the dealership to report the returning leak and await further instructionsDid this help you?
- 8Buying oil filter pliers to remove the housing and replace the o-rings oneselfDid this help you?
- 9Accepting that it is unlikely to cause a problem and leaving them unreplacedDid this help you?
- 10Redoing the gasket installation with a thin film of RTVDid this help you?
- 11Replacing the molded silicone rubber gasket with a fresh oneDid this help you?
- 12Wiping the area clean and checking if the fluid returns after a driveDid this help you?
- 13Tightening the oil filter a bit more by handDid this help you?
- 14Spraying cleaner on the area until it runs clear to test againDid this help you?
- 15Removing the filter to check the gasket for damage, debris, or a double gasketDid this help you?
- 16Replacing the valve cover gasket, spark plugs, and O2 sensorDid this help you?
- 17Cleaning up the oil leak areaDid this help you?
- 18Adding quarts of oil to make up for the lossDid this help you?
- 19using stop-leak additivesDid this help you?
- 20checking or tightening the drain plugDid this help you?
- 21replacing the oil drain plug gasket with an OEM or copper washer and torquing to specDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“a buddy of mine did my friends oil change and its leaking quite a bit, drove and it didn’t fully paint the underside so not an insane amount but still. is it possible the bolt is just not in all the way even though i tried to finger tighten it and it didn’t feel loose or could the oil pan be warped ? advice and ideas needed desperately”source ↗
“Leak is coming from that rounded shape close to the transmission.”source ↗
“How do I redo it? Use a thin yet consistent film of RTV in that area on both sides?”source ↗
“Can I reuse it safely, or should I use a fresh one?”source ↗
“In November is started smoking under the hood. An oil leak at the back of the motor.”source ↗
“Now it has started leaking again.”source ↗
“I’m losing a lot of oil it seems because it is very low. I put 2 quarts in this morning and it’s still not in the minimum.”source ↗
“I just don’t know where the oil is coming from.”source ↗
“Replaced the seal twice and the car is still leaking.”source ↗
“Can somebody throw me suggestions on why the leak won’t stop and what needs to be done.”source ↗
“Could anyone share from experience if the small o rings from the bottom of filter housing are not replaced at the moment of service, is there any imediat danger to the engine”source ↗
“I wiped it clean then went for a 20 minute test drive.”source ↗
“No leak that I could see, but so much overthinking went into those corners I just want to make sure it was sealed properly.”source ↗
“Unfortunately, after I got my car back a couple of months ago, I noticed that there seemed to be a leak near the transmission.”source ↗
“Earlier this week, I noticed drops on my driveway and took a quick look under and noticed that there seems to be a leak near the transmission but am unsure as to what this could be...”source ↗
“I wiped it pretty clean after installation and this is what showed up after a 20 minute drive”source ↗
“I changed oil on my van Saturday, noticed a small oil drop off the new oil filter. Tighten it a bit more. Wiped again and this here was my plan: 1- de the van and check the first again for drips 2- come to reddit and ask about it.”source ↗
“I'm planning to replace the rear main. I already tried nulon rear main stop leak but i don't think it worked. So I'm here to ask for any tips and tricks anyone have, and/or any good videos or manuals which can help me.”source ↗