Which type of bolt head?

dbbd1

dbbd1

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I am having some noise with my right front brakes. (Centric rotors, BMB pads) So, I went and got new, not re-man, calipers. I also decided to get OEM bolts. But for the life of me I cannot find a tool for these.

The threads metric. A 12pt 8mm is too small, a 12pt 9mm is too big. It's not an E-torx. I saw something about "triple square" on the webs but those all looked to be a socket head style, like the inverse of what I have.

Calling @mrblaine

16942949282414686682271707678778.jpg


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16942949766598137760743567424352.jpg
 
dbbd1 said:
I am having some noise with my right front brakes. (Centric rotors, BMB pads) So, I went and got new, not re-man, calipers. I also decided to get OEM bolts. But for the life of me I cannot find a tool for these.

The threads metric. A 12pt 8mm is too small, a 12pt 9mm is too big. It's not an E-torx. I saw something about "triple square" on the webs but those all looked to be a socket head style, like the inverse of what I have.

Calling @mrblaine

View attachment 456395

View attachment 456396

View attachment 456397
Click to expand...

I don't know if it would fit, but an 11/32" SAE is in between a 8mm and 9mm.
 
The 11/32 is a tad loose. I'm still looking but I'll use it for now. I'll use the old trick of covering the bolt head with heavy paper (as a spacer) and pushing the socket on over it.
 
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dbbd1 said:
I am having some noise with my right front brakes. (Centric rotors, BMB pads) So, I went and got new, not re-man, calipers. I also decided to get OEM bolts. But for the life of me I cannot find a tool for these.

The threads metric. A 12pt 8mm is too small, a 12pt 9mm is too big. It's not an E-torx. I saw something about "triple square" on the webs but those all looked to be a socket head style, like the inverse of what I have.

Calling @mrblaine

View attachment 456395

View attachment 456396

View attachment 456397
Click to expand...

I know we're slow to criticize the almighty Mopar but are we willing to entertain the possibility that they've farmed this part out to the lowest overseas bidder? I tend to see this with chinesium crap I get from harbor freight, where the fasteners seem to not really fit quite right on any metric or SAE tools, like they're out of tolerance.

EDIT: later revealed to be OMIX-ADA, not Mopar.
 
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Always willing to entertain out-of-the-box views.

I am going to try assorted 8mm 12pt sockets on the store shelves. McMaster-Carr does not list an 8.5mm 12pt nor a 21/64ths 12pt (5/16th is too small), so it must not exist.
 
dbbd1 said:
Always willing to entertain out-of-the-box views.

I am going to try assorted 8mm 12pt sockets on the store shelves. McMaster-Carr does not list an 8.5mm 12pt nor a 21/64ths 12pt (5/16th is too small), so it must not exist.
Click to expand...

Looks to be an ill made standard 12 point. I am more than pleased to send you some new bolts. OEM equivalent hex flange in the correct length and size. We keep a bunch on hand so when I inspect our new calipers, I can match up the hardware so both sides are the same, make sure the guide sleeves are lubed and get a proper set of crush washers in there with the banjo bolt.
 
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freedom_in_4low said:
I know we're slow to criticize the almighty Mopar but are we willing to entertain the possibility that they've farmed this part out to the lowest overseas bidder? I tend to see this with chinesium crap I get from harbor freight, where the fasteners seem to not really fit quite right on any metric or SAE tools, like they're out of tolerance.
Click to expand...

Where did he mention anything about Mopar?
 
The second picture is pretty blurry (except for the hair on your finger) but from what I can see the points aren't near being at the 90 degrees needed to make a squares so I don't think it's a Tri Square.

I drew these for my son years ago. Yes you'd think the flats on the 12 point would be perfectly flat but at least they're ramping up to grab tighter as opposed to the "square" ramping down and making it easy to slip over.

12 point
12 point.jpg

Not a Tri Square
12 point not.jpg



I'll agree with freedom_in_4low about "chinesium crap" which is what your bolt looks like. Unfortunately it seems too parts being advertised as OEM are far from being actual OEM.

And to finish off this reply, I replaced my front calipers about 5 months apart. Both were Duralast which I'm not bragging about but work fine. The bolts on one side have different size hex head than the other (maybe 12mm and 11mm IIRC). Kinda irritates me but not too much.
 
JEEPCJTJ said:
The second picture is pretty blurry (except for the hair on your finger) but from what I can see the points aren't near being at the 90 degrees needed to make a squares so I don't think it's a Tri Square.

I drew these for my son years ago. Yes you'd think the flats on the 12 point would be perfectly flat but at least they're ramping up to grab tighter as opposed to the "square" ramping down and making it easy to slip over.

12 point
View attachment 457204

Not a Tri Square
View attachment 457205


I'll agree with freedom_in_4low about "chinesium crap" which is what your bolt looks like. Unfortunately it seems too parts being advertised as OEM are far from being actual OEM.

And to finish off this reply, I replaced my front calipers about 5 months apart. Both were Duralast which I'm not bragging about but work fine. The bolts on one side have different size hex head than the other (maybe 12mm and 11mm IIRC). Kinda irritates me but not too much.
Click to expand...

The OEM used 3 bolts commonly. The fronts were a standard hex head with the sometimes hex flange in the mix but always 13mm. The rears were or have always been hex flange in 12mm hex. It is common for the aftermarket to mix those up.
 
B1Toad said:
I hadn't noticed that, learned something new.
Click to expand...

My apologies. I said that wrong. They look tapered due to how the base of the head extrudes up into ramped sections to kill the stress riser at the base of the 6 point lobes. It gives the impression of them being tapered but the actual lobes are straight.

1694531096165.png
 
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JEEPCJTJ said:
The second picture is pretty blurry (except for the hair on your finger) but from what I can see the points aren't near being at the 90 degrees needed to make a squares so I don't think it's a Tri Square.

I drew these for my son years ago. Yes you'd think the flats on the 12 point would be perfectly flat but at least they're ramping up to grab tighter as opposed to the "square" ramping down and making it easy to slip over.

12 point
View attachment 457204

Not a Tri Square
View attachment 457205


I'll agree with freedom_in_4low about "chinesium crap" which is what your bolt looks like. Unfortunately it seems too parts being advertised as OEM are far from being actual OEM.

And to finish off this reply, I replaced my front calipers about 5 months apart. Both were Duralast which I'm not bragging about but work fine. The bolts on one side have different size hex head than the other (maybe 12mm and 11mm IIRC). Kinda irritates me but not too much.
Click to expand...

Yes, the bolts that were on there were 10mm on the upper hex and 12mm on the lower hex.

Since these oddball ones are "supposed" to be OEM, I wanted to start with a clean slate. So I can nail down the brake noise. MrBlaine is coming through with the bolts though.
 
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mrblaine said:
Where did he mention anything about Mopar?
Click to expand...

in his original post (emphasis mine).

dbbd1 said:
I am having some noise with my right front brakes. (Centric rotors, BMB pads) So, I went and got new, not re-man, calipers. I also decided to get OEM bolts. But for the life of me I cannot find a tool for these.
Click to expand...

they don't look like any of the caliper bolts I've seen on a TJ, so if they are indeed Mopar or "OEM" then something has changed, but I don't know where he bought them, either.
 
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