Exhaust Bolt Dimensions? Pictures attached. Chop it or Drill it?

Replacing my stock exhaust with a Borla S type catback and have a bolt seized and will have to Sawzall it and replace it. Anyone know the correct bolt dimensions?

For the curious, I tried PB blaster and wire brush, and then a breaker bar with a bolt extractor. Managed to get the driver side one out, but the passenger side was so seized that the bolt head sheared. At this point I'm going to cut the welded nut off and cut my losses.

 

Take the nut you did get off successfully to either the hardware store or the auto parts store and match it up. Probably 8MM or 10MM.

 

Yeah I'm doing that today. What do you think, just find a nut that will go on it and tighten it down? I don't want to F up the stock flange by chopping that welded nut off. I've heard people do it but I have to be really careful

 

I’m in the exact same boat as you. I went to install my Pro exhaust last weekend and went through my full arsenal of tools with no luck.

I’m waving the white flag and having my local exhaust shop deal with it.

 

You can always drill out the nut threads and buy a longer bolt and put it through, with a new nut on the back. It's a little ghetto, but it works.

 

Yeah I don't care how it looks as long as it seals. That's my main concern. I don't want an exhaust leak before the muffler

 

So that's a loose bolt, nut and washers? Grind off the rest of the head of that bolt (f you have a grinder or a bit you can put in a drill) and it will pop out then replace with like hardware. Even factory if you want. My 4Runner had 3 studs that all broke off and I drilled them out and replaced them with a bolt nut and washers. What a complete PITA that was.

 

X2

 

I believe the nut is welded on.

 

been there, and it sucks. my concern was that even after getting it apart, what is the remaining mating surface going to look like?

 

Cut the nut with die grinder and cutting wheel. Use heavy scotch Brite pad or sanding pad attachment to clean up any remaining nut till all you see is the bolt shaft. Take a punch from the same side and hammer the bolt shaft out. Won't harm the matting surface at all and you won't need to do any drilling etc. Take your time and don't cut or sand the flange to much. I would grind the other nut off same way and bolt new exhaust up with new stainless. hardware

 

Not helpful now, but for anyone headed down this road: You can use a propane torch to heat up exhaust hardware to the point of incandescence and it will come loose very easily. Obviously you’ll want to take care around flammables. A plumbing torch is inexpensive and very handy. That said, if the hardware has corroded to the point that you are taking measures like this you’ll need to replace it anyway.

 

That was my first thought too. But it does look pretty bad.

 

Mine are getting there, although Im looking at the aFe y pipe aswell since the whole thing down isnt looking the best.

 

as I said, not helpful for OP but for future reference for anyone else.