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Rubber oil drain plug?

This is one circumstance when you’ll need to lift the front of the car, and get under it. Per normal safety precautions, use stands to support it, and never crawl under a vehicel supported by just a jack.

When you first thread the hole, do it without the washer. It may be difficult, and that’s to be expected. Since you most likely won’t have cutting oil handy, use regular engine oil or WD-40 or similar to keep the threads oiled while cutting the new threads. Continue to cut threads until you bottom out the bolt. Once they’re cut, remove the bolt, clean any debris, install the new washer and reinstall the bolt to the proper torque specs.

That would be a permanent repair.


The plug does sound like a self-tapping plug and yes it will require some force to get it started. Once you get it started do not try to thread it in with one shot. Tap a half turn, back it up a little, turn some more, back up a little, and so on. This helps to keep the threads clear as it cuts and it will make a cleaner cut.

In addition to the great tips offered by Chaissos and OK4450, let me suggest that it’ll be easier to start it if you use a ratcheting box end wrench. That’ll make it a bit easier to get it as perpendicular as possible and put pressure on the center of it with your thumb.

Alternatively, you could bring it to a tool store as a size reference and pick up a tap with handle in the same size. That’ll be much easier to start and cut with.

And you’ll want to use nylon washers under the new bolt to compensate for any slight lack of perpendicularity or surface imperfections.

I’ve been changing my own oil for 50 years and never stripped a plug yet. If I did though I think I’d fix it properly. I can’t get Lifebuoy soap anymore either-bummer.

It’s been 6 years +/- and by now that oil pan and the car it was attached to are just not so fond memories.

I’d worry that a rubber press-fit stopper would pop out should the pvc system ever fail, creating pressure in the crank case. As long as that never happened , I expect it would work ok. If the oil pan gets scratches on it near the drain plug, it will tend to leak, causing the owner to want to over-tighten the drain plug. I had that problem on my truck until I switched to a thick flexible washer made of a rubber-like material between the plug and the pan years ago, and never had an oil leak since.

Someone revives a 5 year old thread and posts a bunch of links. Why?

A press fit stopper? Maybe, but I would never use something like that. I’ve never stripped a drain plug in my life but if I bought a car with this issue, I would use an expandable plug without hesitation.

My boat and countless others use them to plug up the bilge and rely on them to prevent sinking. Boats costing far more than a car use them and the risk to life is also greater if it fails at sea. If they had any real history of failing, they wouldn’t be used in this more critical application.

They insert PAST the inner lip and when expanded are larger on the inside than the hole they are plugging. No way that is ever coming out unless you take it out. I’ve made the mistake of leaving them in for years and then had a heck of a time getting them out even after completely relaxing the tensioning hardware. The seals in the engine will blow out long before a properly seated expansion plug does. There are plenty of elastic compounds (rubber) that are suited to oil and heat and will outlast your car.

Done properly, I would have no hesitation to use one on the car. In fact, I would think cars would come with them if the expansion plug was not more expensive than the bolt/washer used now…

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I agree, the bolt/washer oil drain plug method isn’t really the best choice for something that the owner diy’er and/or lube shop staff will have to remove and replace many times over the life of the car. Since there’s not a rash of oil puddles along the roadways the bolt/washer method must work pretty well, but something a little more robust and forgiving would be better. Even just a few drops of oil a day is very annoying when I hits your driveway and makes an ugly stain.