Can't find the correct wheel stud

[79vette]

I run 1.25" wheel spacers on the rear axle on my K5 to keep the tires out of the body tub.

One of the studs got messed up, and I am having a tough time finding a replacement. Needs to be 7/16-20 thread, 2" under head length, ~0.555" knurl diameter.

The closest thing I can find is Dorman 610-096.1, but its too short at only 1.4375" and will only engage ~6 threads. I would like to have 1.5 times the stud diameter engaged, which for 7/16-20 would be ~13 threads. I've tried searching on and calling the various auto parts stores, but am not having any luck. Does anyone have a parts catalog that lists what I need?

[kwmech]

What is the number on the head of the bolt?

[79vette]

Originally Posted by kwmech

What is the number on the head of the bolt?

It is stamped "M 12.9", which does not make any sense. This is definitely a 7/16-20 stud. Thats what the wheel spacers were sold as, and thats what the lug nuts I've been using for years are.

I usually interpret "12.9" markings on a bolt to mean Class 12.9 metric hardware, but this is certainly not metric. Any thoughts?

[ACS]

12.9 is the knurl in mm. Go to a .570 with the 7/16-20.

https://www.jegs.com/i/JEGS/555/65101/10002/-1

[79vette]

Originally Posted by ACS

12.9 is the knurl in mm. Go to a .570 with the 7/16-20.

https://www.jegs.com/i/JEGS/555/65101/10002/-1

The knurl diameter is ~.550, which is 14mm. Not 12.9mm.
I was looking at that Moroso part but that stud is 2 7/8" long and would need to be machined to the correct 2" length, and the knurl appears to be about half the length of the knurl on my current stud.

After calling/emailing everyone I could find who sells wheel spacers or hardware, I found a vendor on eBay who did not have the studs I needed listed for sale but was able to get them. The heads on the new ones are stamped 10.9, but they also have a 14mm knurl and seem to match the old one in all dimensions.

If anyone knows what the head stamps mean I would love to learn.

[Getter-Done]

What about these?

They are about 5/16 longer.

Link: https://www.dormanproducts.com/p-463...origin=keyword









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[79vette]

I actually got the correct ones from a vendor on eBay (photo in my last post). I dont have a part number, but the eBay vendor "heavydutyparts" out of St George, UT seems to be able to get anything you need. I sent him a message with the dimensions of my stud and got a new one in the mail 3 days later.

I looked at that Dorman 610-156, but at 1 23/32 length they are 0.28" shorter than my current one (2" under head length) and I was worried about insufficient thread engagement. It would probably work, but I was just a bit nervous