Shortened Catalytic Converter lifespan with valve seal issue?

I've searched a bit and didn't find an answer, though I might have missed it. I see that it has come up in several posts about the hypothetical possibility of shortened Cat lifespan in the setting of excessive oil consumption. I have a 2021 Sig and had the seals successfully replaced @~36k miles last June and no longer need to add ~1/2 qt between changes -- the converter is not complaining. I'm just curious if anyone has seen/heard of issues. Thanks
 
2-3quarts per 1000 miles would probably do that.
Assuming its not fixed in say 9-10000 miles span.
Worse if car is driven short distance and the cat temp can never get high enough vs constant longer distance highway driving.
Plus ther will be lots of blue smoke.

1quart per 1000 miles is usually considered ok-ish by most manufacturers.
Your 1/2 quart per oil changr is not an issue. That is also not excessive.
 
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It is interesting how variable these turbo motors are. I have a 21 GTR with 33k miles. It has not burned a drop of oil in the 4 yrs I have owned it. Have not had the seals done because of this. Others have had crazy consumption. I wonder if I got lucky and the correct seals were used on my motor...
 
Thanks folks. Yes, I was on the very, very low end of "excessive" but with a documented problem, I had the seals done. My 2016 CX5 didn't require topping off between services, come to think of it my Subarus and Highlanders were the same. The 66 Chevy 10 was another story. Just lucky I guess. No way of knowing if the consumption would have remained the same in my Sig or gotten worse over the next 36k miles. Glad to hear that the Cat will be fine.
 
Not "ok-ish" at all!
I'm with you 100%. Why would engineers tolerate a design that when new, leads to less oil than recommended for lubrication before 5,000 miles? When I first read here about the seal issue, some forum participants said their dealers/service centers told them that adding up to a quart between changes was "normal." Didn't pass the simple logic test for me. An error that has now thankfully been remedied at significant cost to Mazda was clearly not ok-ish.
 
I'm with you 100%. Why would engineers tolerate a design that when new, leads to less oil than recommended for lubrication before 5,000 miles? When I first read here about the seal issue, some forum participants said their dealers/service centers told them that adding up to a quart between changes was "normal." Didn't pass the simple logic test for me. An error that has now thankfully been remedied at significant cost to Mazda was clearly not ok-ish.
Up to a quart in between a full oil change is not that bad, especially if your vehicle is specced for thin 0w20. But it's Not normal.
 
That’s an upper limit that sounds primarily designed to protect manufacturers from warranty claims. If an owner tops off with a quart every 1000 mi, that's got to add up. Wild.
 

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