roadmax

1.Picture shows left side, is there a gasket in here?
2.What is the best method to remove what is left from those collar nuts?

twh

Looking at Realoem.com, it seems no. I think it is just a ball and socket arrangement with no gasket. The nut looks ugly in the photo, but the OE nuts are copper and they came off my N52 pretty easily with a impact wrench (I didn't try without the impact). The stud is also replaceable, but it is knurled, so it won't come out easily.

roadmax

Safe approach in this case is having a bolt extractor set, for me size 11 and 12mm saved the day, studs were in very good condition so only replaced 4 bolts with new ones.

gman6262

Mine were like that the first time I took my exhaust off. Start with lots of PB Blast and some heat from a torch. I managed to impact mine off with a smaller 12 point socket - see photos.

seanjordan20

Never use a 12 point socket. It's will round a rusted head. Always use a 6 point it has more surface space.