# Car dopers: what's going on with my car's brakes? **URL:** \ **Category:** Factual Questions\ **Created:** [July 30, 2014, 9:15pm UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446 "2014-07-30T21:15:36Z")\ **Posts on this page:** 13\ **Page:** 2
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [July 31, 2014, 3:16am UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/21 "2014-07-31T03:16:30Z")
> [@Lancia](#): > > Incidentally, the mounting bolts aren’t the same as the pins. The mounting bolts are short, less than an inch long, and quite thick. The pins that the caliper slides on are different. Longer, skinnier. That sounds like the bolts for the caliper bracket. Those puppies go on tight – 85 ft lb torque. It’s a standard bolt. Match the diameter, pitch, length, and strength (8.8 or 10.9 – see [chart](http://www.k-tbolt.com/bolt_chart.html)). If you’re lucky, you may find them at a hardware store. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [July 31, 2014, 3:22am UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/22 "2014-07-31T03:22:49Z")
> [@Lancia](#): > > I ran down to the auto parts store, and they didn’t have the mounting bolts. The dude behind the counter said they didn’t even have an entry for them in their computer. That surprises me. I’ll go to the other stores in town tomorrow. Caliper bracket bolts are not a normal replacement item. I wouldn’t expect any auto parts store catalog to list them. I wouldn’t even be surprised if the dealer didn’t stock them. Take the old bolt with you and match it as I described above. ---
**Author:** ![Lancia](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lancia/32/17174_2.png) [@Lancia](https://boards.straightdope.com/u/Lancia)\ **Post date:** [July 31, 2014, 3:39am UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/23 "2014-07-31T03:39:32Z")
> [@Gary\_T](#): > > That sounds like the bolts for the caliper bracket. Those puppies go on tight – 85 ft lb torque. > > It’s a standard bolt. Match the diameter, pitch, length, and strength (8.8 or 10.9 – see [chart](http://www.k-tbolt.com/bolt_chart.html)). If you’re lucky, you may find them at a hardware store. Yeah, finding my notes from last time, they have a 93ftlb spec. And yes, you’re right. It’s the bracket that came loose. Apologies if I wasn’t clearer on that. I’ve always removed the bracket (with caliper) instead of removing the pins. ---
**Author:** ![Lancia](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lancia/32/17174_2.png) [@Lancia](https://boards.straightdope.com/u/Lancia)\ **Post date:** [July 31, 2014, 3:53am UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/24 "2014-07-31T03:53:49Z")
Dafuq? I just went out and pulled the other bracket bolt. it was finger tight. I’ll happily admit that my torque wrench may be inaccurate, but those things sure as hell were tighter than that. I wonder if my car is trying to commit suicide, and take me with it. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [July 31, 2014, 3:59am UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/25 "2014-07-31T03:59:05Z")
There’s no need to remove the brackets if just changing pads. I only remove them if I’m replacing rotors. A bolt that’s significantly less tight than called for can vibrate loose. ---
**Author:** ![Gatopescado](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gatopescado/32/5711_2.png) [@Gatopescado](https://boards.straightdope.com/u/Gatopescado)\ **Post date:** [July 31, 2014, 4:07am UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/26 "2014-07-31T04:07:37Z")
> [@Lancia](#): > > Thanks for the replies, everyone. > > Holy shit. I had my kids in my car today! Its okay, as long as you don’t leave them in there. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [July 31, 2014, 8:44am UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/27 "2014-07-31T08:44:12Z")
There’s usually a brake specialist parts/repair shop in a reasonable sized town … they’ll have the pin. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [July 31, 2014, 1:18pm UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/28 "2014-07-31T13:18:04Z")
> [@Isilder](#): > > There’s usually a brake specialist parts/repair shop in a reasonable sized town … > they’ll have the pin. It’s not a pin, and it’s not a specialized brake part. It’s a regular bolt, probably about 10x1.5x25 mm. The caliper didn’t come loose from the caliper bracket. The bracket, with caliper attached, came loose from the knuckle. ---
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [July 31, 2014, 2:25pm UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/29 "2014-07-31T14:25:21Z")
Were they originally installed with locking compound? Does the service manual spec replacement of the bolts or some loctite? That, or your wrench is way off. Good you caught it before any real damage… of any kind. ---
**Author:** ![RivkahChaya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rivkahchaya/32/8919_2.png) [@RivkahChaya](https://boards.straightdope.com/u/RivkahChaya)\ **Post date:** [July 31, 2014, 3:36pm UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/30 "2014-07-31T15:36:59Z")
Check the front brakes, ASAP, and use Locktite from now on. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [July 31, 2014, 4:20pm UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/31 "2014-07-31T16:20:47Z")
> [@RivkahChaya](#): > > Check the front brakes, ASAP, and use Locktite from now on. From post #19: **“I had a professional do the front…”** ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [July 31, 2014, 4:50pm UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/32 "2014-07-31T16:50:14Z")
> [@Lancia](#): > > I do have a torque wrench, but it is one of those old beam-style wrenches. I have no idea how accurate it is, but I’ll be borrowing a click-type when I put this thing back together…I’ll be taking both sides apart this weekend and re-checking the torque on all the bolts. > > I just went out and pulled the other bracket bolt. it was finger tight…I’ll happily admit that my torque wrench may be inaccurate, but those things sure as hell were tighter than that. Just so you know: A torque wrench is only accurate in measuring tightening torque **WHILE THE BOLT/NUT IS BEING TURNED**. Using it on a bolt that’s already tight will give a much higher reading than what the bolt was actually tightened to due to the force required to overcome static friction. Make sure the pointer or clicker registers **WHILE TURNING THE BOLT**. **YOU CANNOT MEASURE WHAT AN ALREADY TIGHTENED BOLT WAS TORQUED TO WITH A TORQUE WRENCH.** You **MUST** first loosen the bolt (about one turn), then retorque it in order to know that it’s tightened to the proper torque. When more than one bolt is involved, it’s best to tighten them in stages. For a spec of 85 ft lb’s, I’d first tighten them all to about 25, then all to about 55, then all to 85. ---
**Author:** ![kaylasdad99](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kaylasdad99/32/3398_2.png) [@kaylasdad99](https://boards.straightdope.com/u/kaylasdad99)\ **Post date:** [August 1, 2014, 1:52am UTC](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446/33 "2014-08-01T01:52:39Z")
> [@Lancia](#): > > Thanks for the replies, everyone. > > So I pulled the left wheel off, and… > … the goddamn brake caliper had _came off!!!_ Dang. That was going to be my guess, until people started talking about shock absorbers and parking brakes and stuff. Glad you found it. [Previous page](https://boards.straightdope.com/t/car-dopers-whats-going-on-with-my-cars-brakes/694446.md?page=1)