Anyone found a cure yet for the "CX-5 weeping drainplug syndrome"?

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2023 CX-5 Premium; 2018 Mazda 3 GT hatch
I just pulled the underbody oil change cover off @2500 miles since the last oil change and the damn drain plug was weeping again as it has twice before. So this time I actually used a torque wrench set @30 pounds and I would say I was maybe 5# shy the last time I hand tightened it without using a wrench (using a new dealer-supplied washer). In 50 years of changing oil I have never had this problem with a simple drain plug washer and have never used a torque wrench! I'm beginning to wonder if it's the damn washer is too thin. The washer on my Miata is about twice as thick and I have used the same washer for over 100k miles with nary a leak. Anyone taken their CX-5 in for the dealer to resolve this?(help)
 
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I had this problem after the first oil change that I performed. I initially thought that there was no crush washer installed. So I installed a new one not realizing that the original was still there. After troubleshooting the leak I discovered the original washer was painted on so it did not come off until I did some prying. The original washer had also deformed at some point so no matter how tight it was it was never really sealed, causing the leaking. 2 or three oil changes later I am having no problem with the leaking using appropriate torques. My ford's don't have crush washers at all.
 
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I went with the Fumoto in my sig.
That's a rather expensive way to resolve a piddly problem, but it is a way. On the other hand, what's to stop the Fumoto from leaking and how can one get the proper tightening torque on one?
 
I understand it isn't a cheap option in comparison. I bought it for convenience though. I think the gasket used with Fumoto probably has a greater chance of not leaking over the long term.

I was able to get proper torque with torque wrench and 19mm crows foot.

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25ft lbs puts it right at the correct position as well.
 
Last oil change I put some thread sealant on the drain plug and used my torque wrench to be sure it was tightened correctly. So far no weeping.
 
I just ordered some of the Permatex product MikeM suggested. I'm not going to take any more chances with this thing. Hopefully, after re-torqueing the drain plug mine will be OK until my next scheduled service in 2500 miles. I'll continue to monitor it though.
 
The Permatex is the smartest thing I've ever seen Mike post.

That said, I'm glad I'm not the only one. My undercarriage tray was greasy to the max last night, when I went in for LOF. This time, I used a new crush washer. Inspecting the existing (leaky) washer, it looked like it'd been over torqued by the dealer and badly malformed. If they aren't over torqued, crush washers can be used multiple times and still create a good seal.
 
The Permatex is the smartest thing I've ever seen Mike post.

That said, I'm glad I'm not the only one. My undercarriage tray was greasy to the max last night, when I went in for LOF. This time, I used a new crush washer. Inspecting the existing (leaky) washer, it looked like it'd been over torqued by the dealer and badly malformed. If they aren't over torqued, crush washers can be used multiple times and still create a good seal.
I have to agree with your first comment.(yes) That said, let me ask you a question. You seem like a technically savy guy. Why then would you (and others here) persist in calling these aluminum flat washers "crush washers" when they in no way fit the definition of such a device? My Nissan Frontier used a crush washer on the drain plug and it was an extruded copper design that actually crushed (collapsed) to form a seal when torque was applied to the plug. These washers that Mazda uses are simply malleable aluminum that conform to the shape of the mating surfaces (and apparently not very well) on either side. If you want to think of this as "crushing", that seems a bit of a stretch.
 
My Nissan Frontier used a crush washer on the drain plug and it was an extruded copper design that actually crushed (collapsed) to form a seal when torque was applied to the plug. These washers that Mazda uses are simply malleable aluminum that conform to the shape of the mating surfaces (and apparently not very well) on either side. If you want to think of this as "crushing", that seems a bit of a stretch.

I've got a huge bag of those Nissan crush washers. I assumed early on Mazda was using the same thing.

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That's them. I've owned three Mazdas, starting with a 1994 Miata and none have used this type of washer.
 
Haha! You're absolutely right. Mazda's aluminum washers really aren't crush type. Call them that out of habit, I guess.
I agree, they really seem to have little to no "crushing" action. But, I think that's apart of what makes them reusable, if they're not abused.

I find all of this pretty strange, because I never ONCE replaced the washer on my Speed6 drain plug. I had that thing for, what, 6 years? And I never replaced it, and it never wept. So, I was a little surprised to see the CX-5 weeping so quickly. Though, after inspecting it the other night, it was clearly malformed from the dealer over torquing. Replaced it, and as of last night, no more weeping.
 
I find all of this pretty strange, because I never ONCE replaced the washer on my Speed6 drain plug. I had that thing for, what, 6 years? And I never replaced it, and it never wept. So, I was a little surprised to see the CX-5 weeping so quickly. Though, after inspecting it the other night, it was clearly malformed from the dealer over torquing. Replaced it, and as of last night, no more weeping.
And that's the same experience I had on my Miata. 110k miles of reuse and it never leaked, but the washer itself was about twice as thick as the CX-5 washer. Keep an eye on your newly installed washer. I thought mine was sealing properly after my last oil change, but after 2500 miles I checked it and it was leaking again! Next time I will use the Permatex plug sealer for sure.
 
Maybe, it's a good idea, to replace the washer at every oil change, or just get another copper universal washer.
 
Maybe, it's a good idea, to replace the washer at every oil change, or just get another copper universal washer.
I have replaced the washer on two out of three oil changes. Ironically, the only one that didn't leak was the first change on which I reused the original washer. What might make sense is to try one of the older style (thicker) Mazda aluminum washers, but I have not seen any noticeable distortion on any of the washers I have used, so I'm confident the Permatex sealer will do the trick.
 

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