Stripped Thread

Hello all,
My brother asked me to stop by his house tonight after work, seams he's replacing the front brake pads on his 1996 Chevy 1/2 ton pickup. The reason
he wanted me to stop by was he said he was concerned about not being able to remove one of the caliper bolts. He told me on the phone that the bolt was difficult to remove, and didn't want to screw anything up. So I stopped by and he's right. the bolt didn't want to come out, you could feel the threads grinding when you tried to turn it.
Sooo the bolt is now out and there are about half of the threads left in the spindle. I looked up the caliper bolt on the web and it's a M11 x 1.50 thread, I then went to the helicoil web site, seams they don't make a helicoil that size. Any suggestions on how he might fix this short of replacing the spindle?
Thanks Brian
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Just out of curiosity, who is the last person/company that did the brakes? The reason I ask, bolts don't strip coming out, they strip going in, so the last fellow who ran that bolt in there did the damage. Given the thicness and hardness of the material used for the spindle whoever it was must have run that thing in there crooked with an impact wrench. If it was a business I'd take it up with them and have them address the issue.
Regarding fixing your problem, I can't think of anything off the top of my head if helicoil doesn't make one in that size. Caliper bolts are pretty application-specific so finding a slightly larger one and drilling/tapping to a larger size would be pretty difficult. Also, for the same reason it would be hard to find a longer bolt and run it thru the spindle and just pop a nut on the other end with some loktite blue.
Doc
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He bought this truck about two years ago, and this is his first time taking the calipers off. I guess either the previous owner did it or someone that they took it to. I'm going to check with a couple of import dealers and a few machine shops and see if that size thread insert can be had. I have no idea why GM would pick such a goofy size for the caliper bolt threads.
Brian
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Found a repair kit in that size.
http://tinyurl.com/7hwb9
What's interesting is the manufacturer that's stated on this web site is Helicoil. When I was on Helicoil's web site they didn't show one. Oh well.....
Brian
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Are the threads in the spindle or in the caliper? Easy to replace the caliper with a rebuilt, only a little more expensive than buying pads to get a loaded caliper (pricing is goofy). Options on a damaged spindle is to upsize to the next size bolt if possible, replace with a used unit from wrecking yard, or weld the hole up then drill and tap to original specs, which pretty much meaning taking it out to do the job right.
el Diablo wrote:

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Threads are in the spindle, we hope to get a helicoil kit in M11 x 1.50 thread. So far the only kit I've located is in the UK. But that's fine I will order from there if I have to.
Brian
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Since half of the threads are still there I would buy a tap and run it through the threads. Put a NEW bolt in with some magic marker on the threads so you can see just how much is there. If half is still there I would use some Loctite thread former to make new threads in the spindle. MAKE SURE YOU USE THREAD RELEASE. If you don't forget about getting the bolt back out without a torch. Steve W.
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Follow up, I found out that they make over size thread caliper bolts. They have a self tapping thread, we have it installed and are back in business. When the heliciol kit comes in we'll replace the OS bolt and fix it correctly.
Brian
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