I've searched everywhere on this forum and couldn't find the answer to this, so maybe someone here can advise. I'll be putting an axleback exhaust in and since the nuts are welded into the stock muffler, I'll need a couple of 12mm nuts. I just need to know the correct thread size before I buy the wrong ones, thanks for the help.

 

why would you need new nuts? the nuts are wleded onto the stock midpipe.
you should be able to reuse the stock spring bolts to install a new axel back. direct bolt on.

 

Hi,

If the bolt head is 12 MM, its usually a 8 MM shank on the bolt. I don't have the thread specs handy, but its usually the 'common' one for 8 MM.

If you're headed to the hardware store, you might want to consider replacing the nuts and bolts with stainless steel 5/16ths hardware. Shanks are within a couple thousandths of an inch and will come apart much easier in the future (no rust). Otherwise, consider using Never-Seize.

You may even be able to get metric in SS if you have a good hardware store.

Bring the bolt with you?

John

 

Night - AJR usually sends a couple of nuts and washers with their new exhausts (mine is used), so I was under the impression that I will need it for the muffler side. I'll have to check first before I buy it then.

Race - Thanks for the tips, I thought 8mm would be it. I'll probably unbolt first to see if I'll need the nuts anyways and bring it along.

Edit: For anyone's later reference, yes it is an 8mm shank and a 1.25 thread size, so you need a M8 x 1.25 nut. I recommend that you get a flanged nut if possible and an 8mm washer that has a wide ring so it does not fall through an exhaust's bolt holes.