Cat back flange bolt

I know this has been asked multiple times but I have tried for 2 days to come up with a solid answer even asking the dealer. On a 3rd gen, mine being a 2019, what is the size bolt being used on the flange right before the muffler? Have seen 3/8 but can’t lock that down. I want to switch mine out with grade 8 ss when I switch my cat back exhaust out.

 

1. Drive to Home Depot/Lowes/Ace
2. Bring wrench, take bolt out
3. Bring bolt inside, match bolt with SS bolt
4. Buy bolts, replace in parking lot
5. Beer

 

On my 2017, I had it apart once to do the axle dump. It is most certainly metric. 14mm?

See attached.

 

Set a crescent wrench to fit that nut and take to store. Find your nut, find your tool and find your Beer

 

stainless for all those time you take your exhaust apart....

 

I have always replaced exhaust nut and bolt assemblies with grade 2 not grade 8.

My logic being that down the line it is easier to just snap the grade 2 bolt and replace it with a new one rather than mess around trying to remove and reuse it.

If those nuts on the flange are welded on obviously that method won't work.
In that case use the best anti-seize you can find.

 

Thanks for the help in this thread! Snapping the old rusted welded on nuts was super easy. A little dremmel to flatten the surface, new grade 2 washer and nut. C-clamp was definitely needed to compress the spring. All in all a super quick job.

Now if I could only get used to the drone of the TRD Exhaust... its a little loud at initial acceleration for me.

 

And +1 for buying the actual bolts from the dealer since there is a ridge that holds it tight against the forward flange. A common hardware store bolt would "float" between the two flanges. Not sure if it matters or not.