Author Topic: Installing M12 x 1.5 studs on rear axle hubs  (Read 273 times)

SoupMan

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Installing M12 x 1.5 studs on rear axle hubs
« on: March 03, 2021, 10:41:07 AM »
Hi,

I purchased a set of 10 M12 x 1.5 studs to replace the M12 x 1.25 in the rear axle hubs. Reason I want to do this is that the front now has the Corvette C7 bearings and those are M12 x 1.5. I would like all of the studs to be the same.

Is there a trick to drilling the holes to fit the new studs?  I have a drill bit that is 0.01 inch smaller than the stud neck.


ryeguy2006a

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Re: Installing M12 x 1.5 studs on rear axle hubs
« Reply #1 on: March 03, 2021, 11:43:48 AM »
What I would suggest is finding a set of studs that has the same knurl size as the current studs that you have. Or if that size isn't available make sure that you actually buy a reamer as they are less likely to wobble. I know this because I used a drill bit to bore out my front hubs to 39/64" which is the correct size for my knurl, but the bit must have wobbled. Even though I used a drill press. After 500 miles I checked my front wheels and 3 of the 10 were loose and able to be pushed out by hand.

My 2cents.

Also for what it's worth, the rear axles are hardened, and be prepared to go through at least 5 drill bits.

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JJ 109

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Re: Installing M12 x 1.5 studs on rear axle hubs
« Reply #2 on: March 03, 2021, 03:29:43 PM »
I re drilled mine in the rear and it was a bitch. Was just using a cordless drill.

Apparently opened one too much, and the stud started spinning in the rear axle/hub trying to remove the rear wheel and liked to never got it off. Had to cut, grind air chisel out from the rear under the car. *@&$&#&@

0.01 is within the 0.006 to 0.016 recommendation.

Reamer is not a bad idea.
JJ
76 pro tour project
Twin Turbo LS1
Detroit

SoupMan

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Re: Installing M12 x 1.5 studs on rear axle hubs
« Reply #3 on: March 03, 2021, 03:41:32 PM »
So you guys did a good job at getting me my answer. I will stick with the 12 x 1.25 for now.

I ordered another set of lug nuts. I'll just deal with it. I don't want that trouble which is what I expected would happen if I did this myself. Whenver I replace the rear diff, I'll have a machine shop fit the axle shafts with ARP studs.

Thanks!



 

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