Stretch bolts

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T.Hanson
Posts: 1696
Joined: Wed Jul 26, 2006 7:39 am

Stretch bolts

Post by T.Hanson »

I have read these are NLA, and very expensive. Coincidentally, I have rebuilt three sets of brake calipers and one engine using the same bolts I removed out of ignorance. I'll be danged if the cars haven't stopped nicely for five, ten years and the engine has run great for six, or whatever.
What's the deal ?
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Mike W.
Posts: 2790
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Post by Mike W. »

Unless they snap or feel "wrong" when you're installing them I wouldn't worry about it. If you've wrenched a lot you can feel when a bolt is nearing it's limit.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
PatinaBeforePolish
Posts: 352
Joined: Sun Jan 18, 2015 1:22 pm
Location: Baltimore, Md.

Post by PatinaBeforePolish »

I just purchased new ones from Wallosthnesch. I think they were about $8 each.
79 528i
76 530i - Stored since 1992, can it be brought back to life?
86 944- 2023 project
78 F150- Everyone needs a truck
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Joe Boston
Posts: 88
Joined: Sun Nov 27, 2016 12:11 pm
Location: Winchester, MA

Post by Joe Boston »

I purchased them here
https://www.belmetric.com/hex-bolts-cla ... 6nv2es38v5


make sure you get Grade class 10.9 they are the same as OEM.
if you doing a complete caliber rebuilt, I purchased the "O" rings at PMB Perforamce
http://www.pmbperformance.com/catalog/i ... 694936.htm

hope this helps
1980 E12 Ascatgrau 5 speed
2001 E38 740 Black
2012 F12 650 IC black
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Mike W.
Posts: 2790
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Post by Mike W. »

I just did all 4 calipers a few months back and I think all the kits except one had the little O rings in there. So you might want to check the kits before ordering new O rings.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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