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CTS-V Caliper Came Off

Confusingboat

Confusingboat

New member
Alright, so about a month ago I dun did the swap, and they've been working famously. Just enough time to get them broken in and clamping like they should.

Then last night on my way home from the grocery store, after braking at a corner (thankfully just down the road from my house), my driver's side caliper came off with some initial grinding and a nice big THUD. I had a friend with me so I limped the car home while he watched the caliper to make sure that it didn't jam up or anything while it sat on the bottom of the wheel. To lighten the mood I rolled all the windows down, put my hazards on and blasted Low Rider while creeping along at 2 mph to confuse any innocent passersby. Great success!

Anyways, I just got my car in the garage today and I'm just about to go out and look at it to see what happened. Earlier in the day I had slush buildup in both front wheels causing massive vibrations, which I had to pull over to clean out both on my way to AND from work. F*****g Minnesota weather... I'm not sure if this had anything to do with it, but it was the only thing out of the ordinary that had occurred beforehand. I'll update with more information as it becomes available.
 


what came off, just the caliper, or the bracket and caliper?

dont think snow would cause that to happen. maybe try some loc tight on the new bolts this time, and wrench them a bit tighter.
 
when i got my car from a previous owner, they obviously didnt wrench the bolt tight enough that holds the caliper bracket to the steering knuckle. it fell out and as i began to pull away from a stop and corner like you described, grinding then bam, except my caliper wedged in the wheel and locked up my wheels. had to jack up the car right there in the middle of the street and unbolt the wheel to free it up. luckily i had a bolt the same size in my tool box and limped home.

you cant torque down 73 ft. lb. with a regular hand ratchet. i believe that is what i remember the tq spec being. when i got it to my shop, i threw on loctite and pulled out my big 1/2" snap on torque wrench and cranked them down.
 
i have a small bottle jack in my took box. its handle fits my 3/8 ratchet perfectly. i used it to put my brackets on, i just took them off to do a hub, and i needed the pipe to take them back off. i go to good and tight, then maybe a 1/4 turn extra. not to the point of breaking the bolt, but tight.

the lock tight on my trucks caliper brackets were so tight, ( from the factory) i needed to use a 1/2 breaker bar with a 4 foot jack handle to break them free. they were 22 mm bolts iirc. and they were snug and thick feeling the whole way out, talk about a work out lol
 
Alright, so I've figured out what happened. The bottom bolt came out (which is still intact) and then the top bolt broke the caliper because all the torque was on that one spot. I also noticed that the F-body bolts that I used only threaded into the caliper about half way, so I'll be looking for some longer bolts. That combined with the intense vibrations probably expedited the bolt coming loose. I'll also put Loctite on the bolts when I replace them.
 


Ya you need to get the longer bolts don't use the fbodys... mine stick out the other end of the caliper holes by like 1/4 of an inch lol.. plus I think the cts-v ones are TTY bolts... good thing you didn't mess anything up
 
by reading im guessing you didn't drill and tap the caliper bracket to use the grand prix caliper bracket bolts? are you using a sleeve with the f-body bolts?
 
Yeah I used bushings and I just picked up some thread locker. Gonna go get some longer bolts after I'm done eating my Five Guys :P I also can't find any local places that carry CTS-V calipers...what gives?
 


[h=1]ACDelco 172-2308 for $87.18 on Amazon. Plus Prime is free 2 day or $3.99 for one-day which says Tuesday delivery.[/h]
If you want to do that let me know if that is the right parts number.
 
I have Prime, and that's not the part number I ordered before. The one I ordered before is out of stock at Amazon (except from their marketplace sellers) which is why I'd have to order it from somewhere else. But if that's an alternate part number for the same part then I'll just order that.

EDIT: just checked. That part is for the rear.
 
youre suppose to use cts-v bolts, not f-bodies, even though drunkies thread says either or.
 
I ordered Mfg. 172-2287 / OEM 89047727. Also, the F-body bolts were working fine until one decided it wanted me dead. I went to Menard's though and picked up some thinner washers and some longer grade 10 bolts, so I should be good to go once my new caliper arrives.
 


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