Here's a new one...was changing rear rotors and pads on a '14 IS350 F-Sport. Everything went smoothly until I started re-torquing the bolts holding the caliper mounting bracket (two 17mm bolts that are each torqued to 92ft lbs). Both went in just fine but one bolt ended up straight up tearing the thread out of the receiving socket well below the torque spec. See pics of carnage. Of course Lexus will not warranty this although I don't see how it wouldn't have happened in their shop. I live in New England, so I'm guessing some corrosion might be to blame, or a defective part. Curious if anyone has ever run into this, definitely a curve ball on an otherwise routine job.

 

That is definitely not normal. Something was wrong with the threads at some point.
If you had overtorque'd it, then the bolt head should have snapped off because the threads should have held up.
Clearly the threads were weak for some reason.
92 is the correct torque, so either the bracket had an issue, or someone else was in their prior to you and screwed something up.
Maybe it was cross threaded and someone tried to Tap it straight?.

 

Yeah, at first I thought the bolt had snapped, but it's totally fine, no damage at all to the male thread. Bolt still had the green loctite from the factory so I believe these are the original parts (car has 42k miles). I'm puzzled since there's still thread left in there (you can see it in the pic), but not enough to really grip.

 

The most proper fix would be a new bracket...still very strange.

 

That's the plan, will be a few days since it's not a commonly stocked part. Serves me right for not wanting to pay dealer $600 for the job :-)

 

LOL...serves you right!! LOL!!!

 

it almost looks like someone before has stripped the threads on that bracket and has installed helicoils in (but not done properly).. that's all I can think of to have threads pulled clean out like that.

 

Wow - that does look like it! I just went through the service history before I had this car (I'm second owner) and here's this little ditty from 2014:

SERVICE: CUSTOMER REQUEST BRAKE INSPECTION
DESCRIPTION: CUSTOMER REQUEST BRAKE INSPECTION ~ ~CHECK BRAKES STATES THAT THEY WERE SQUEAKING SPORATICLY PLEASE CHECK AND ADVISE ~ ~ ~ ~6156 BRAKES ARE WORKING PROPERLY NO PROBLEMS FOUND AT THIS TIME

I think this would have potentially involved removal of the bracket to properly check pads and shims. Taking this to the dealer, thank you.

 

keep us posted on how it it goes with your dealer.

 

Not to take the wind out of your sails...but you'd be lucky if they even took the caliper off for what's written above. There wasn't even a brake measurement.
If they did really check it, then they would have taken the caliper off and just removed the pads...the bracket only needs to come off if you are taking the rotor off...or for some reason you need to work on the bracket itself, off the car.

It could be a helicoil, but hard to tell from the pic. If it was the stock thread, then you should be able to break it apart by hand...a helicoil, not so much, it would be a lot stronger. You would need to cut it apart with cutters.

 

Do you think the threads are possibly pressed into that hole from the factory (vs being cut into the part)?

 

Here's another pic of it. Seems pretty tough, I can bend it with my fingers but I think pliers would be needed to cut. What's the chance this is just how it comes from the factory? I just don't get how it would have gotten there otherwise. Will check other side tomorrow. At this point, it's a matter of curiosity too!

 

Factory should be the threads cut right into the bracket. But I've not seen that washer with the fingers on a Toyota before.
The washer is supposed to be there...but I wonder why.
I'm curious too.

 

Because so much thread came out it kinda suggests something like a helicoil. It would make no sense to press threads into the bracket from factory...it would be just bizarre.
I might ask someone at the dealer I know.

 

That would be awesome. Another thought that came to mind is that when I did the front brakes last year there were yellow match marks on the equivalent bolts up front showing the position from the factory. I don't recall seeing those, going to pay extra attention when I get back in there since missing match marks on bolt head but presence on the bracket might indicate that bolt was swapped at some point.