I recently tried to replace my rotors on my 08 TL Type S and got the top caliper bolt broke loose and was turning fine, but the bottom bolt broke loose and then after about a turn locked up and really did not seem to want to turn anymore with a half in breaker bar on it, so i just tightened them back up and decided to wait. I was very weary about putting an extension pipe on it cause I don't wanna snap the bolt off. I am wondering if there is rust and what not on the very tip of it that is causing it not to want to turn anymore. Has anyone ran into this issue before and snapped the bolt? If the bolt does snap off will the caliper come off he knuckle or will i have to pound it out? Any help would be appreciated. Thanks.

 

The good news is that if the lower bolt were to snap, it would've been initially when trying to break it free, which you've already done.
My money is on that it won't snap, it'll just ruin the threads in the caliper when unthreading. Then you can helicoil/time-sert it for fresh threads. Ask me how I know.



Get a can of either PB-Blaster or AeroKroil (harder to find), and let that sum'bish lower bolt soakkkkkk for like a day or two. Then with your 1/2" breaker bar, try to work the bolt back and forth, back and forth, back and forth, and you might be able to make some progress.

You might as well go ahead and order 4 new caliper bolts now, just to be safe.

 

Thanks for the info. I will take another stab at it one day soon.

 

Probably part of the thread from the caliper is stuck to the bolt (common on aluminum parts), so it will be hard to turn all the way, and most likely nothing can't be done about it. (no heat or pb blaster will unstuck that)

Bolt will be fine after cleaning / running the die or thread chaser of proper size on it, but might need to repair threads in the caliper like twokexlv6coupe wrote.