While I was changing the pads and having the rotors turned on my '06 WRX the driver's side caliper mounting bolts stripped out the threads on the inside of the caliper. I only used air to remove the bolts. I started the bolt by hand and used a Gear Wrench to snug it up and finally a torque wrench to tighten it all the way down. The factory service manual states to torque the bolts to 114.3 ft/lbs. As I'm torquing it to spec, the threads pull out. I drilled out the hole and put in a Perma Coil insert (which was $50 bucks and had to call 15 places to find :unamused. The hole with the insert held fine, but then as I'm torquing the other bolt, it pulls the threads out at around 90 ft/lbs and actually pulled a small chunk of the materiel off of the caliper around the mounting tab on the caliper. I've read where people have had problems with the aluminum Brembo calipers pulling threads out, but the 4 pots are cast iron. I'm wondering if there was some problem with the materiel or the casting :dunno. BTW, the car has 32k miles and this was the 1st time the calipers have been off the car. I did get it fixed but it was a huge PITA! Can anyone confirm the correct torque for the caliper mounting bolts? 114 ft/lbs seems awfully high.
Correct me if im wrong but I believe the caliper bolts are stainless and have to be replaced when removed. The threads stretch as you remove them causing you to crossthread when you re-install.
Something like that would make sense, but I have never seen a set of the bolts for sale other than a dealer. They are a funky thread pitch 12mm x 1.25. I would think that more vendors would stock them along with other brake parts if they had to be replaced when doing basic maintenance like replacing rotors. I will check into if they are stainless.
you're are still in factory warranty make them replace it. I have had no problems with mine and damn I didn't know the torque specs on those were so high I am certain mine are WAY less.
Well he was still under factory warranty, but I doubt they will replace them since he was the one who did the work. They'll probly just tell him that he's SOL.
i was gonna say, i think i specifically remember lowe's carrying that pitch. (used to work in hardware at lowe's). probly cost you .50 to get the bolts you need
I said they were a funky pitch because I had so much of a problem finding a tap or the Helicoil / Perma Coil inserts locally. That and my neighbor who is a mechanic brought home two decent sized tap and die sets and there was no 12 x 1.25 in either one. Everyone was telling me that 12 x 1.5 or 12 x 1.75 was a more common bolt. I do know that 12 x 1.25 is a common spark plug size though. I'm gonna try to source some bolts before I remove the calipers again and I will definitely check Lowes.
they are grade 8 IIRC. stainless wouldn't really work in this application. I've always re-used them, and I've never heard of having to replace them, but I could be wrong.
Stainless is still STEEL so i doubt it stretches by removing it Brake bolts arent stainless - ive not seen any that are. They have to meet certain grades OP i would check the torque specs and make sure your torque wrench has the same units I would drop a drop of wax to use as a lube and will eventually go away.
For the 02 the service manual has it at 80 nm or 59 ft lbs. I doubt it is much different on the newer ones. Sounds like you may have misread something.
thats what i have on my notes but im not sure without looking at the bolt and where its located Type: Bolt Dim: Length: Head: Hexagon Grade: 114 Ft-Lbs 1368 In-Lbs 154.56 N-m Connects: Caliper To Steering Knuckle Years: All Vote Record: Vote Note: Gen II - FRONT 17 Inch Type here is fsm page http://www.ixizconcept.com/fsman/front_discbrake.pdf
Wirelessly posted I don't think I had to replace any bolts on mine when i had the rotors out for a bit.