10x1.50 12x1.50 and I even think I saw 14x1.50. The second number isn't an issue depending what due I use but the shaft diameter does i.e. 10mm 12mm 14mm. So does anyone know for sure??
Thanks
Beau
I think I saw most guys recommending using a 12mm to start and then using a 10mm, probably because you have to work out the knurled surface of the shift lever. Depending on how committed/complicated you want to get, it might be easier to cut off the knurled section of the shift lever, thread the smooth section for a shift-lever extension (like one from SickSpeed), and then order a knob that will fit the thread pattern of the extension.
Thread pitch will matter depending on who you are ordering from, which shift knob you are ordering, and whether or not you will be getting a separate reverse-lockout adapter or getting the shift knob with a built in adapter.
I do not know if the diameter of the Sonic's Reverse-Lockout Collar is the same as a Ford Mustang, but it might be close. I'm just too tired right now to delve into the interwebs to find out atm.
Just for reference:
Knobs designed for the 2015-2017 Ford Mustang Manual 6 have a M12-1.25 thread with a reverse lockout recess.
Knobs for the 2016/2017 GT350 Manual 6 have a M10-1.25 thread with a reverse lockout recess.
I got the above information from this site:
Twisted Shifterz
They can make custom knobs with reverse-lockouts, they just have to know the diameter of the lockout collar.
Hope that helps somewhat. Keep in mind, I am no expert in this department as I primarily drool over wheels all day.