I'm about to start my Lebaron brake upgrade and when I was about to press in my longer studs I noticed that I had 2 different sized wheel stud nurled bases. One hub rotor had the smaller stud i assume a factory replacement rotor and the other one had the larger wheel studs I assume aftermarket part rotor. Has anyone come across this and if so what part number wheel stud did you use for the larger stud
Thanks

If you are converting OEM rotors to hubs, then the longer stud is Dorman PN 610-323 Qty:10

However, if you are using new aftermarket hubs, then the holes for the wheel studs are sometimes larger and you need another stud option. Here is a side by side of the stock fiero wheel stud and the one from the aftermarket hubs with the larger shank:


So if stock fiero wheel studs don't fit the hub hole, then use this part number: Dorman 610-427. It has a stepped shank and will fit the hole in the rotor while still retaining the M12-1.5 thread pitch.
Here is what these studs look like installed. Notice it has slightly more than 1 7/16" threaded length, but more importantly notice the protruding shank:


To use these wheel studs you will need to bevel or enlarge the backside of your brake rotor holes so they slide over the enlarged shank.

quote Originally posted by fieroguru: So if stock fiero wheel studs don't fit the hub hole, then use this part number: Dorman 610-427. It has a stepped shank and will fit the hole in the rotor while still retaining the M12-1.5 thread pitch.

That might work for people with 5x115mm GM hubs who would wish to convert them to 5x4.5" by machining oversized stud holes, slightly offset from the existing ones.

[This message has been edited by pmbrunelle (edited 10-25-2020).]

Once again this website and the experts who answer questions like mine...THANK YOU! Thanks for the photos and part numbers. I will be getting those wheel studs tomorrow!