exhaust nut

[juanbenae]

i installed the cat-bypass this weekend and in removing the old nuts i found that they seemed to be a brass type material. this made since in that there would be less of a rust issue but i did not get the slit in the nuts. it was a groove/slit/cut all the way through the nut to the threaded area just beyond the hex area where the wrench/socket would grip. it was about 1/3 of the way around the nut.

does any body know what this slit is for? is it an expansion deal that will let the nut heat and cool without wanting to loosen up?

they were all like that and original install hardware.

by the way, no rust, did not have to cut 1, and used them all again. the life of a garage queen!

[Jim Sims]

Based on your description it appears to be a prevailing torque lock nut for higher temperature service. The section below the slit was likely slightly distorted to provide an "interference type" locking action. Jim