I will be ordering a Y-pipe soon and read several write ups on installing it. I think I will be able to tackle this myself. Acording to Maximadriver.com, you need a 22mm wrench to remove the oxygen sensors.

The largest metric wrench I have is 18mm. Can I use a large (good quality) adjustable wrench? Or do I have to buy a 22mm open end wrench or flare nut wrench? I also have standard wrenches up to 15/16ths, is there a standard size that is close enough to work.

I definatly do not want to round off the oxegen sensor, but I don't want to spend money on a wrench I will only use once either.

Yeah, there is a standard size one that will work without problems, but for the life of me I can't remember what it was. For some reason 7/8's jumps to the front of my mind.

However, the correct wrench would be a good investment. When I swap y-pipes I plan on picking up a 22mm.

7/8" flarenut works fine. They have sockets for this, but for a one time use, i wouldn't buy them. Wrenches work just fine.

I used a 7/8" O2 sensor socket, but a crescent wrench or something will work just as well.

They do make a special O2 socket for it, but I just used a 22MM open end.

If ya got the wrench dont bother with the special O2 tool. I mean how often you gonna use it that a wrech wont do for now anyway.

SuDZ

Just make sure you put Anti-seize on the thread when you put the O2 sensors into the new Y-pipe. If you don't you'll have a hard time getting them out, if you ever remove the new Y-pipe.