this post was submitted on 17 Apr 2024
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Ran into this while doing an oil change, why is this like this? Why is there a chunk of thread missing? Vehicle is a 2019 Buick Cascada. Based on the look of things, At one point before it came to me the threads got cross-threaded or stripped, there was an attempt to retap and rethread the hole. There was a HeliCoil installed, And it came out while I was removing the drain plug.

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[–] TragicNotCute 11 points 5 months ago (1 children)

I don’t know, but if I give a wrong answer, you should get a better right answer from someone else.

I googled it and this is what I found:

Looks like it's at the low point in the pan to make the drainage more complete.

[–] littlebluespark -1 points 5 months ago

IANAM, but it took one glance at the photo to know why there was a drainage route through the threading: um, drainage.

[–] espentan 4 points 5 months ago* (last edited 5 months ago) (1 children)

I think it's just to allow for more of the spent oil to drain from the pan. Seen it on many different cars.

Edit: Keep in mind that not having a full set of threads makes the plug more sensitive to over torquing. Drain plugs do not require a lot of torque. Look up the specs for your car and use a torque wrench if you're uncertain.

[–] focusforte 2 points 5 months ago (2 children)

So, you think this came from the factory like this?

[–] espentan 4 points 5 months ago (1 children)

Yes, I'm quite certain it did.

[–] focusforte 1 points 5 months ago

Interesting 🤔 I've seen some with drain holes in the threads, but this is the first one I've seen with such an excessive cutaway.

[–] HootinNHollerin 2 points 5 months ago

Missing nsfw tag lol

[–] not_that_guy05 2 points 5 months ago* (last edited 5 months ago) (1 children)

What threads? Am I missing something here cause I see that oil pan threads are no longer there....

If this is a shit post, well done.

[–] focusforte 1 points 5 months ago (1 children)

Yeah, the striped threads are what had me looking closer than usual, but not related to the question I had. I was more curious if that cause Cut away section was factory or part of the thread repair that some one attempted before I got it

[–] not_that_guy05 3 points 5 months ago

That's a factory cut due to the pan being lower than the hole for drainage.