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Overtighten drain plug on girlfriends impala

I was tightening the drain plug on my girlfriends impala and I overtightened it. I was applying pressure after it started resisting and felt it strip very slightly. I stopped immediately after feeling the smallest bit of slip. Is it trashed or will it be ok? I usually stop upon resistance. I didn’t realize i was overdoing it. It was the tiniest bit. I didn’t really test it after cause I didn’t wanna over do it more.

You’ll find out at the next oil change.


No doubt. I’m tempted to jack it back up and loosen and retighten it. Probably not good driving around with it too tight.

If it not leaking for now just leave it alone and check the oil level daily for a week or two. Then check once a week and watch for oil on the ground also.


Leave it alone.

It’s better to have it too tight than too lose.

And what if you remove the plug and find it can’t be tightened to prevent it from leaking oil?

Now you have time to come up with a method to repair it if it is stripped.

Such as this.



Thank you. In your experience have you found that a slightly stripped bolt can perform its functions properly? I took it past the point of resistance probably the smallest amount as possible

Does the vehicle have an aluminum oil pan or a steel oil pan?


I wouldn’t trust it left that way myself. I might if it was my own car, I’d keep an eye on the situation, but not if it was on somebody else’s car. I expect you already know the damage the engine would incur if it failed. Any auto machine shop can repair this problem for you. Not gonna be that expensive.

I believe it’s aluminum.

You think I should loosen and retighten?

If I had that problem I’d drain all the oil out (save it in a clean catch pan lined with a plastic trash bag), then have a leisurely look- see at how serious the problem is. If you decide its ok after that, use a new gasket when re-tightening the drain plug, and only to the approved torque.

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Why new gasket?

The new gasket is crushable, and this helps to prevent leaks and over-tightening. Buy 10 of them and you’ll have a new one on hand for the next 10 oil changes.


Head to the nearest auto parts store

Buy the correct oil drain plug for the car

And when you do the next oil change, if you need to replace the drain plug, you’ll have it on hand

The oil drain plug will come with the new gasket

That way, if the gasket is shot, the new oil drain plug will take care of the problem

If the drain plug threads are shot, the new one will take care of the problem

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The Timesert is a neat repair but I think it is overkill. If the pan is aluminum, it is the threads in the pan that will fain, not the ones on the drain plug. I would just go to a parts store and buy an oversize self threading drain plug. If you don’t know if the pan is steel or aluminum, just try sticking a refrigerator magnet on it.

we don’t even know that op stripped the pan threads at this point

A magnet will tell you whether it’s steel or alumin(i)um. A torque wrench will keep you from over-tightening in the future.

The torque spec on that thing is most likely 18 ft-lbs. Some 3.8L engines were 30 ft-lbs but, either way, it isn’t very much. Generally, people way over-tighten the drain plug. I’m guilty of it - there’s something comforting about knowing that thing is tight, right?

And pray that the drain plug doesn’t fall out. Most people motor on and trash the engine. In that case she will likely be an ex-girlfriend…

Thank you lads!! Oil level is stable and there is no drip. I should repeat that I overtightened it to the smallest amount imaginable surely. It was like the smallest amount of slip possible and I gave it a little twist after and it felt solid. I just don’t understand the science behind stripping.

If it slips a little bit but then feels solid afterwards, does that mean I stripped a percentage of the threading ?