Is this too much rust on my exhaust? And an AFR sensor question.

[theirare]

I went to replace the AFR sensor on my 2001 SR5 (with a Denso 234-9002 Air Fuel Ratio Sensor) and found some nasty rust on the 12mm bolts holding the sensor in place in the exhaust pipe and some odd bolts that don't seem to be threaded like normal. Check it out here:

http://i1380.photobucket.com/albums/ah173/theirare/101514024_zps5a6f31fc.jpg

It may be hard to see, but the bolts seem smoothed like they were made that way. Is there a specific part number for these nuts/bolts that also need to be replaced with the sensor?

Also, when I was down there I noticed a lot of rust on my exhaust, cats, and muffler. Is it too much? While I don't want to replace my exhaust system if I don't have to, it is a mod I have been wanting to do for some time. An excuse to replace the entire exhaust system is enticing, but my goal would be to replace it with something that provided the same amount of performance (or a little more) and a quieter, stock sound. Any suggestions on stock-like exhaust options out there? Thanks.

 

[MStudt]

I don't see any rust.

 

[TheDurk]

That all is in great shape compared to mine. The threaded part is a stud that is part of the bung, and that is the way the end is. There is no bolt. The nuts are part No. 90179-08059, but any stainless M8-1.25 will do. Hit the nuts with lots of PBBlaster and you should be able to get them off with a 6-point socket.

 

[theirare]

TheDurk, thanks for clearing that up and I'll try your suggestion.

That's great to hear about the rust. I saw those bolts rusted to the exhaust and it made me want to replace them with shiny ones. Glad I don't HAVE to buy a new exhaust yet.

 

[JayRolla]

And where is this rust again? LOL