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First off I got to say, these 4 piston Caliper Brembo’s that came on this model STI’s suck and could have been designed better. Here’s a few reasons why for your education:
1. The calipers should have never been threaded. The design should have been bolt through and threaded to the caliper bracket.
2. Steel bolt going into an aluminum housing is definitely a no-no. Under heat they expand and contract at different rates. When the aluminum heats up it hardens onto the steel bolt which causes the threads to get stripped when backing out the bolt.
3. They used a course thread 12x1.5 bolt. It should have been a fine thread that gives you more threads per inch. That gives the bolt more material to grab on to which equates to a stronger bold and less likely to strip out.

My story: I just recently redid my brakes and 3 of 4 bolts got stripped out. The Subi shop down the street from me wanted $100 EACH HOLE and that was if I brought the calipers in. They highly recommended me to NOT use heli-coils which I agree because they’re only a temporary fix. My next thought was might as well do a brake upgrade since I’d be spending so much but that’s at least $1500 just fronts. So I came across these Time-Sert’s and checked out the reviews and they’re pretty solid!

- This is how I properly repaired my stripped threads on my 08 STI Brembo’s with a Time-Sert kit: I recommend using a drill press to get more accurate and straight holes. I used 3 large grip clamps to hold down to the drill press base and drilled away. You can use WD-40 on the bit to help but the material is so soft and if they are stripped out enough like mine it’ll drill through easily and fast. Next drill bit (with the collar) is to make a cut out for the flare end of the sleeve to seat into. It has a limiter so you don’t cut too much out. I used the drill press for this as well and learned you don’t have to cut down to the limiter since the flare on the sleeve isn’t that deep. The next two bits I recommend doing by hand using a tap and dye set handle to maintain even and equal pressure. The third bit is the Time-Sert specific tap for the sleeve. I didn’t use any lubrication because as mentioned before, the material is soft enough. Every 1-2 full turns back off a little to break the cut pieces off. BE CAREFUL!!! At the end of my fourth hole a piece of aluminum got stuck in between the teeth of the tap. I used a razor blade to break it off and got it out before it stripped the new threads I made. Now you’re ready to insert the sleeve with the last bit. This is actually tapered so as you drive it in it pushes the sleeve into the caliper and seats it. Start with threading the sleeve onto the bit at least one full turn. I put a few drops of red medium lock-tite in the middle of the threads. Drive it through all the way and do not back out, go one direction. I already test fit them on and they are solid!
Good luck to everyone going down this road! To be honest it looks intimidating but was a lot easier than I thought. I decided since the calipers were off to upgrade all the brake lines and switch to Motul Dot 4 as well so I’m still waiting for those to come in along with a vacuum brake bleeder. If anyone else has any other suggestions or recommendations please chime in.
 

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idk if I’m the only one with this issue, but my time sert calipers actually failed on me. I went to take off the caliper after 2-3 years of getting them done and the whole insert snapped and tore a big hole in its place. A shop did the insert so not sure if it was their fault. Now I might be stuck having to buy a new caliper
59508
 

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that normally only happens if it was installed incorrectly...it should be pretty tight gettin it installed to prevent pulling out...sometimes i have seen in high rust areas things out of the ordinary happen like that...but just size up on the OD an redo the time sert...they are very high quality and prefer them significantly to helicoil...
 

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Discussion Starter #4
idk if I’m the only one with this issue, but my time sert calipers actually failed on me. I went to take off the caliper after 2-3 years of getting them done and the whole insert snapped and tore a big hole in its place. A shop did the insert so not sure if it was their fault. Now I might be stuck having to buy a new caliper View attachment 59508
Wow I’m sorry to hear that. Ya like what Jedi03 said, the shop could have installed them incorrectly. It may as well could have been a number of things as well. Using anti-seize is preventative, if they used lock-tite might not have been the best choice. Torquing then down correctly could play a factor too. The book says something like 110lbs but my shop says that’s too much and they do about 90-92lbs and have never had returned issues.
 

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1) this used to be extremely common. "Everyone" experienced more or less what you did. Cost me a $500 calper once back around 2013?

First off I got to say, these 4 piston Caliper Brembo’s that came on this model STI’s suck and could have been designed better. Here’s a few reasons why for your education:
1. The calipers should have never been threaded. The design should have been bolt through and threaded to the caliper bracket.
2. Steel bolt going into an aluminum housing is definitely a no-no. Under heat they expand and contract at different rates. When the aluminum heats up it hardens onto the steel bolt which causes the threads to get stripped when backing out the bolt.
3. They used a course thread 12x1.5 bolt. It should have been a fine thread that gives you more threads per inch. That gives the bolt more material to grab on to which equates to a stronger bold and less likely to strip out.
Yeah the AL alloy is soft actually almost butter soft!. But, ALL the above is incorrect. The reason so many people used to have problems - and some still do is exactly what you later wrote: that the FSM had an error and everyone, even the factory stripped em. course no one realized till they had to replace pads. There are dozens of similar posts on the web including a few here. Examples(not all):

2/2010

10/2007

Torquing then down correctly could play a factor too. The book says something like 110lbs but my shop says that’s too much and they do about 90-92lbs and have never had returned issues.
ALLDATADIY still shows 114 ft lbs. I though the correct torque was around 80. Can't find it at the moment

My story: I just recently redid my brakes and 3 of 4 bolts got stripped out. The Subi shop down the street from me wanted $100 EACH HOLE and that was if I brought the calipers in. They highly recommended me to NOT use heli-coils which I agree because they’re only a temporary fix. My next thought was might as well do a brake upgrade since I’d be spending so much but that’s at least $1500 just fronts. So I came across these Time-Sert’s and checked out the reviews and they’re pretty solid!

- This is how I properly repaired my stripped threads on my 08 STI Brembo’s with a Time-Sert kit: I recommend using a drill press . . . If anyone else has any other suggestions or recommendations please chime in.
My experience:

Used a drill press and trashed a caliper because it was not straight. Did others by hand.
Used Heilicoils and they are still fine 7 years and 150Kmi later.
I am aware that Timeserts are supposed to be better, but they are not as readily available. and Heilicoil knockoffs at regular Automotive chains are inexpensive. Also for Helicoils and I think this will be the easiest safest cheapest fix is to use Heilicoils and not drill at all! The alloy is that soft. Just tap and install the coi!.
 

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Discussion Starter #6
1) this used to be extremely common. "Everyone" experienced more or less what you did. Cost me a $500 calper once back around 2013?



Yeah the AL alloy is soft actually almost butter soft!. But, ALL the above is incorrect. The reason so many people used to have problems - and some still do is exactly what you later wrote: that the FSM had an error and everyone, even the factory stripped em. course no one realized till they had to replace pads. There are dozens of similar posts on the web including a few here. Examples(not all):

2/2010

10/2007



ALLDATADIY still shows 114 ft lbs. I though the correct torque was around 80. Can't find it at the moment



My experience:

Used a drill press and trashed a caliper because it was not straight. Did others by hand.
Used Heilicoils and they are still fine 7 years and 150Kmi later.
I am aware that Timeserts are supposed to be better, but they are not as readily available. and Heilicoil knockoffs at regular Automotive chains are inexpensive. Also for Helicoils and I think this will be the easiest safest cheapest fix is to use Heilicoils and not drill at all! The alloy is that soft. Just tap and install the coi!.
Thank you for chiming in but I’m not following why ALL three of my reasons are not valid. Two different metals together getting hot/cold day in day out that’s why aluminum heads aren’t good on a cast iron blocks. On our off-road vehicles we run bolt through the caliper and threaded to the bracket. Makes perfect sense imo. And to run a course thread over a fine thread?! Just doesn’t make sense, torqued or not torqued a finer thread with be stronger and less likely back out for any reason. And to use a helicoil over a time-sert?!?! It’s basically just a wire that’s coiled up and it’s not a solid piece. I mean if it worked for you that’s great and all but I wouldn’t trust that on my brakes. Yes you can keep your calipers on and do pads all day long but when you need them rotors turned or replaced those helicoils will fail!
 

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Ohh and about the Time-Sert readiness availability: you are right your local parts store might not stock them but I was able to get mine off amazon in 2 days and was able to do all 4. I even bought extra sleeves just incase I messed up haha, which I didn’t. I’m not sure how you trashed one before because it wasn’t straight but I am by far no means a mechanic with fancy tools or anything but I consider myself decently mechanically inclined and like you mentioned it’s buttery soft so I just went slow and watched to make sure it was going in straight. Tapped it by hand, went in perfect and I have honestly never tapped new metal before. Fixed a few threads after powder coating but that’s about it.

I think if I could do this anyone can!!!
 

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+1 they are not hard to do...i drill all my stuff by hand, which i dont recommend, even i shouldnt as i have medical issues with mine....i am frustrated as we used to be able to get timesert from the local parts stores as my dad always got em just whenever he needed them...i still remember my first time with helicoil/timeserts....removed head from early 30s packard and it was helicoil in all the stud holes, dad showed me and discussed the difference and capabilities of both...we then drilled out the holes for the timesert and installed....was super easy even in that monster of cast iron! lol, helicoil works, is cheap and readily available but just as stated above i personally wont run it...i also have trouble getting the coil to install w/o distorting lol
 

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And to use a helicoil over a time-sert?!?!
I thought I made it clear I was not in any way anti-Timersert.


It’s basically just a wire that’s coiled up and it’s not a solid piece.
Uh yeah - and they do their job well enough that in high end applications where they are commonly used to strengthen threads in soft materials during manufacture, or say a build.


I mean if it worked for you that’s great and all but I wouldn’t trust that on my brakes. Yes you can keep your calipers on and do pads all day long but when you need them rotors turned or replaced those helicoils will fail!
Worked for thousands - for long before Timeserts became known (or even invented?) My brakes have been apart several times in my STIs 255K miles. The only time I had an issue was the very first disassembly! I think I stripped three bolts of the eight. never an issue again - cause I didn't tighten em to over 100 ft lbs.

But while it is not the issue, I'm fairly confident that using fine threads will not gain enough support material behind the threads to make the fastening stronger. Using an insert does this by making the hole larger. The increase in circumference provides a much larger amount of soft metal to withstand the force. Fine threads in that application will also be more likely to have bind issues with any small particles. STI owners have all too frequently snapped the caliper bolts from binding, after being partially stripped. One of my three snapped.

One nice thing about Timeserts is that they offer over sized inserts for buggered holes :)
 

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This crap happened to me a couple years back to a rear caliper when i had to do brakes. It was friday night after work and a bolt snapped on me. I spent alot of time trying to extract it but eventually i was able to get it out. I actually ended up replacing the bolt with an extra that i had anticipating something like this happening. Luckily for me, the threads weren't to far gone and i was able to tread it and just tighten it down. Its been years and its held up fine. I did have a time-sert kit in my tool box but i believe its a kit for the fronts calipers, part # 1215 M12 X 1.5 bolt patern. The kits are different for the front and rear calipers if i remember correctly. I also believe that the factory manual is wrong about the torque spec. I think i remember torqing everything down to like 80-88 ftlbs.
 
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