wheel studs
Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 8,887
Likes: 981
From: Whitby Ont.
wheel studs
I need some help with this one.. recently changed out the rear hub/bearing on my C5z, Purchased a SKF from RA, I have longer studs in my hubs, and I
assumed i would knock the SKF studs out and install my longer ones, well that didn t go so well as the SKF holes are bigger and the OEM knurled portion of the stud is smaller . I believe stock is M12 x 1.5, i need M13 i believe. as the hole is .51. And am struggling to find studs that will work on the SKF hub. and they can t
help me except to say the hole is .51, which equates to M13 I think.. so my question is.. does anyone know where i can find M13 x 2 studs ?
TIA Al
assumed i would knock the SKF studs out and install my longer ones, well that didn t go so well as the SKF holes are bigger and the OEM knurled portion of the stud is smaller . I believe stock is M12 x 1.5, i need M13 i believe. as the hole is .51. And am struggling to find studs that will work on the SKF hub. and they can t
help me except to say the hole is .51, which equates to M13 I think.. so my question is.. does anyone know where i can find M13 x 2 studs ?
TIA Al
Le Mans Master
Joined: Oct 2007
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From: Akron Ohio
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How did you get the old studs out? Standard GM studs have a 0.509 knurl and I have not heard of SKF requiring a different stud. Scrolling through ARPs catalog I couldnt even see a 0.511 or 0.512 knurl that would work on a 0.510 hole. Something sounds off.
Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 8,887
Likes: 981
From: Whitby Ont.
"Standard GM studs have a 0.509 knurl:" i don t understand why the longer Dormans did not work.
i looked at a lot of sites also.. 13m is not common.
Last edited by walleyejack; May 3, 2022 at 10:05 PM.
Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 8,887
Likes: 981
From: Whitby Ont.
I took it apart somewhat, don t feel like disassembling suspension again right now.. but the SKF holes are definitely larger than OEM.
hoping these pics can show the difference.
Last edited by walleyejack; May 4, 2022 at 12:01 PM.
Pro
Joined: Mar 2002
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From: Allen (DFW) Texas
Can't tell much from the pics but Kubs is correct, the standard knurl diameter is 0.509. Specs on the ARP M12 x 1.5 studs show a knurl diameter of 0.509 (same as stock), with a required bolt hole size of 0.493 - 0.503. But specs on the SKF BR930198 hub show a 0.510 bolt hole size (as SKF stated) so I understand the confusion. Even the ARP web site https://tech.arp-bolts.com/wheel-stud-fit.php clearly says the hole should be .006 - .016 smaller than the knurl diameter, so a .510 hole would require a stud with a knurl diameter of .516 - .526.
I've always changed studs myself and have never had an issue with the ARP M12 studs so I'm not sure what's going on here. Don't know who "RA" is that you purchased the hubs from but maybe you could reach back to them and ask if they offer that same hub with studs installed, and if so what studs to they use.
I've always changed studs myself and have never had an issue with the ARP M12 studs so I'm not sure what's going on here. Don't know who "RA" is that you purchased the hubs from but maybe you could reach back to them and ask if they offer that same hub with studs installed, and if so what studs to they use.
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Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 8,887
Likes: 981
From: Whitby Ont.
Can't tell much from the pics but Kubs is correct, the standard knurl diameter is 0.509. Specs on the ARP M12 x 1.5 studs show a knurl diameter of 0.509 (same as stock), with a required bolt hole size of 0.493 - 0.503. But specs on the SKF BR930198 hub show a 0.510 bolt hole size (as SKF stated) so I understand the confusion. Even the ARP web site https://tech.arp-bolts.com/wheel-stud-fit.php clearly says the hole should be .006 - .016 smaller than the knurl diameter, so a .510 hole would require a stud with a knurl diameter of .516 - .526.
I've always changed studs myself and have never had an issue with the ARP M12 studs so I'm not sure what's going on here. Don't know who "RA" is that you purchased the hubs from but maybe you could reach back to them and ask if they offer that same hub with studs installed, and if so what studs to they use.
I've always changed studs myself and have never had an issue with the ARP M12 studs so I'm not sure what's going on here. Don't know who "RA" is that you purchased the hubs from but maybe you could reach back to them and ask if they offer that same hub with studs installed, and if so what studs to they use.
Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 8,887
Likes: 981
From: Whitby Ont.
Le Mans Master
Joined: Oct 2007
Posts: 9,682
Likes: 3,432
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
If you want you can drill out the hubs a little more and use a Toyota stud. They are also M12x1.5 but have a 0.565 knurl diameter. They press into a 14mm hole.
The Official ARP Web Site | Kits (arp-bolts.com)
The Official ARP Web Site | Kits (arp-bolts.com)
Melting Slicks
Joined: Nov 2017
Posts: 2,306
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Never even saw this. I had the same issue when I replaced mine with SKF all around a couple years ago and try to warn everyone I can when they ask about hub replacement. At the time, I scoured the web for a suitable replacement to no avail. I ended up returning the SKF rears, picked up Duralast rears, and swapped out the studs out with no issue.
In my search at the time, I came across a review left on Summit for the same part that said he had the same issue on his C5Z. Luckily I was able to return the hubs for a refund after I carefully put the supplied studs back in...lol, but yeah this is important info for people swapping out their hubs.
In my search at the time, I came across a review left on Summit for the same part that said he had the same issue on his C5Z. Luckily I was able to return the hubs for a refund after I carefully put the supplied studs back in...lol, but yeah this is important info for people swapping out their hubs.
Race Director
Joined: Oct 2004
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Never even saw this. I had the same issue when I replaced mine with SKF all around a couple years ago and try to warn everyone I can when they ask about hub replacement. At the time, I scoured the web for a suitable replacement to no avail. I ended up returning the SKF rears, picked up Duralast rears, and swapped out the studs out with no issue.
In my search at the time, I came across a review left on Summit for the same part that said he had the same issue on his C5Z. Luckily I was able to return the hubs for a refund after I carefully put the supplied studs back in...lol, but yeah this is important info for people swapping out their hubs.
In my search at the time, I came across a review left on Summit for the same part that said he had the same issue on his C5Z. Luckily I was able to return the hubs for a refund after I carefully put the supplied studs back in...lol, but yeah this is important info for people swapping out their hubs.
Melting Slicks
Joined: Nov 2017
Posts: 2,306
Likes: 747
The studs work just fine if you want stock length studs. We're talking about swapping them out for longer studs. Either for racing purposes or just so you can safely run larger spacers to give you more wheel fitment options.
Yeah I didn't really look at the measurent pictures, but they're definitely larger. Can't really measure them without popping them out of the hub haha, I agree. I did measure mine while they were out, but I didn't document the actual size.
Yeah I didn't really look at the measurent pictures, but they're definitely larger. Can't really measure them without popping them out of the hub haha, I agree. I did measure mine while they were out, but I didn't document the actual size.