Trouble getting 17mm caliper bolts off on a 95 camry

[justin_o]

I need to remove the caliper assembly and rotor from my front, passenger side hub to replace a sheared hub bolt (I cross threaded a lug nut and didn't realize it. Tried unscrewing it against resistance and the bolt sheared at the surface of the rotor... argh!).

So I got a replacement lug nut and hub bolt from a local Toyota dealership thinking I would just take the caliper assembly and rotor off like the tutorials said to do but I can't get the 17mm bolts off. The 14's are fine. I used a 12-point 17mm socket and a foot-and-a-half long torque wrench AND a soft mallet to break the bolt out. I tried some WD-40, I even froze the bolt and metal using LOX from a can of compressed air. I could not get either bolt loose.

I gave up and went back to google. I found out a 6-point socket is preferable to a 12-point on such a heavily torqued bolt and that I might need to use a breaker bar. I'm concerned that I will strip the the bolt. Should I take it to a mechanic and give up on DIY or should I try a 6-point bolt and a breaker bar? My concern is that further attempts at DIY will result in a hefty bill at the mechanic to undo my "repairs" to my car

I should mention that my brake pads were replaced 3 months ago and the rotors machined by a service center with a good reputation. They are the last guys to touch my 17's so I'll be taking it to them regarding this. But I would like to just do this myself. I don't know what the correct procedure for tightening these bolts is or what the service manual specifies as the correct torque.... but I wouldn't be surprised if the guy just used an impact wrench at high pressure and over-tightened the bolts.

Anyway, thanks in advance for any help/advice. I didn't think getting these bolts off would be so complicated.

[hooRAH]

Well, I can write pages on either working on brakes or getting tough bolts out, but I'll make this short and you can ask more questions if I don't explain enough.

#1 - Turn the wheel. Have you turned the steering wheel to allow yourself a better position to put the breaker bar on the bolt? If the wheels are pointed straight, you only have a few configurations that a 2' breaker bar cat fit without interfering with the ground or other parts of the car. Having the wheel turned makes this much, much easier.

2- dont use a torque wrench. I've had caliper carrier bolts on cars with more than 600ftlbs of torque. That can very easily break a torque wrench (or cause it to become uncalibrated). Use a MASSIVE breaker bar or impact gun to get the bolt off. The bigger the better on the breaker bar, not because of the torque advantage (although it is nice), but because the longer the arm, the less shear force you have to apply for a given amount of torque. The shear force is what causes the wrench to slip off and round the bolt head.

3 - PB blaster, not WD40. WD40 is a water dispersant to reduce rust, not a lubricant. Get the PB blaster, let it soat.

4 - Make sure you're as straight as you can be relative to the bolt head. You want a perfect 90deg angle and the force to come straight up (hard to describe, hope you know what I'm saying). That means no ujoints, swivels, extensions, etc on the breaker bar. You want the force going straight into the handle, not at an angle. #1 (turning the wheel) helps with this.

5 - At any repair shop, there is only 1 torque setting for caliper carrier bolts - full on with the impact gun. Thats just the way they do them, and thats probably why theyre on there so tight.

6 - If your tools are from Walmart or Target, forget it. I've ripped 19mm sockets in half trying to take caliper carrier bolts off of a jeep. Better have some good craftsman stuff or impact grade sockets. Impact sockets are heavy and expensive.

7- If you folllow all the other suggestions, you shouldnt strip the bolt head or shear it off. You will probably destroy your tools before you shear the bolt head off. Now, if the wrench keeps slipping, you can round the head, and thats easy to do.

This is not an impossible job, lots of people do their brakes. But without tricks and experience, it can be frustrating. Keep at it, and buy the tools if you need them. You'll thank yourself. Any more questions, just ask. I do this stuff all the time.

[justin_o]

Thanks for all the tips. I did turn the wheel to get a better angle on the bolts (I picked up that tip from a tutorial on how to replace hub bolts ).

So... I'll get some PB, a in impact grade socket, and beefy breaker bar and go in for round two.

[trdcamry00]

If you can get the right angle, try to put a pipe over the breaker bar after you put some WD or PB. Has never failed me yet. If I'm lazy I use my best friend.

[justin_o]

PB and a breaker bar with a good six point socket did the trick. I took off the caliper assembly, the brake pad assembly and the rotor to get access to the hub. The bolt sheared at the surface of the hub so I didn't have a good exposed surface to strike with a hammer. The articles I read on replacement made is sound like the bolt should come out: "You do not need to beat on the bolt; just keep hitting it mildly until it pops out the back of the hub" (from http://www.stealth316.com/2-wheelbolt.htm).

Maybe if more than a millimeter of bolt were sticking out I would have been able to apply more pressure. I tried centering a smaller bolt on the surface of the hub bolt and hitting with a mallet but that didn't work. It sure didn't feel like it would just "pop out", it felt pretty snug in there.

Any suggestions? I'd hate to take the whole thing apart again and still not get the bolt out.

PS: I got quite a scare when I couldn't get the caliper back over the brake pads because the piston was depressed too far. But a little googling and scrounging for a c-clamp and I was able to push it in far enough to get over the pads. I've never changed brake pads before and didn't know what to do. Thank god I didn't attempt this on a rear wheel because I don't have a piston depressor tool (I read you can twist and push with a pair of pliers but it's not a good idea). On the bright side I figured it out

[Mike Gerber]

"Thank god I didn't attempt this on a rear wheel because I don't have a piston depressor tool (I read you can twist and push with a pair of pliers but it's not a good idea). On the bright side I figured it out."

For future reference, on Camrys the rear caliper pistons work the same as the fronts. You do not need any specail tools to turn them back in. They just push straight back in, the same as the fronts.

As far as removing the broken stud, you can put another tool on it, like an impact socket extension, and hit that with a few good blows from a good hammer or mallet, to force the stud out. Spraying some PB Blaster on that too and allowing it to soak a while should also help.

Good luck.

Mike