I bought a borland true fit muffler system and after cutting off all the welded bolts (just after second o2 sensor and just after the muffler) I cleaned everything up, new metal rings and installed the true fit with new bolts and used the red thread lock stuff. When I started it up I noticed a lot of air coming from the gap around the bolts where it connects just after the second o2 sensor. I didn't weld anything but think I need to stop by a muffler shop and have them put a big gob of metals in the bolt slots to seal it. Or is it a sign that the seal isn't meeting correctly? I don't mind them welding it air tight but wondering if something else is wrong. The back connection after the muffler doesn't leak air at all. It was the original Toyota muffler with 178000 miles and finally got a couple rust holes. Gonna miss it - it was so quiet which is what I really want.

 

Yes. Sounds like the gasket is not installed correctly, is the wrong gasket, or things are not bolted together squarely.

 

Think I can be lazy and just have it welded and not worry about it? Seems like it might be a simple solution. Too lazy??