How to get "frozen" caliper bolts out??

You | 3/20/2017 | Me

[Paul R.]

Advice needed: It's either corrosion or a gorilla with a wrench, or both, but I cannot get the brake caliper bolts on our Ford Explorer out. FoMoCo exacerbates the problem by using bolts with shallow heads, so it is difficult to keep a socket on them. I have tried various penetrating oils such as PB Blaster, smacking the bolt heads with a medium hammer, etc. to no effect. More info. in my 1st comment...

[Paul R.]

Well, I’ve been “attempting” on this for 3 days now, so it seemed like time to get ON the web (sporadically, I’ll admit) and get some advice.

It looks like the PB can get “in” on either side of the bracket. But, the shallow hex head on the pin really does limit getting good torque on it.

If there are no threads at the end of the pin opposite the head, then SURELY I can beat this thing!

I’m 1st going to try grinding off the chamfer on the socket & going “two person” with me trying to keep the socket on the hex head, and all 95 lbs. of my wife on the breaker bar. (That way, if it slips and I get whacked, only I get whacked.) I also may try laying my hands on an air impact wrench — that plus turning the wheel might get “in there” with the impact wrench.

Then, maybe the heat as advised... well shoot, “gotta” find something else to work on for a bit, or maybe eat lunch. A line of T-showers just arrived, and this IS a “driveway” project!

[Paul R.]

Of course, some here are suggesting “Time to take out a bottle, Jack and...”

More seriously, I think the bigger problem is simply keeping the socket on the shallow hex head.

[Paul R.]

That’s a good point about flame under a car.

The main bolts are really locked up too... And this was a garage kept vehicle of which my mechanic buddy said the lack of visible corrosion was remarkable. But these pins / bolts have been a real bugger for me, compared to past vehicles I’ve worked on.

[Tunehead54]

Stupid question but if they’re pins then turning them will do nothing - you have to drift them out ... ?

[HandyDandy]

You really should go to YouTube to see how your caliper body is connected to the caliper bracket. The slider pins that you are talking about don’t have any external threads. They are what slide. The caliper is bolted to them (by internal threaded hole in end of slider). I’m guessing that you have run into this small caliper-to-slider bolt being frozen. You may also have a frozen slider. It slides into a blind hole in the caliper bracket and is sealed from the elements by the rubber boot. Ideally, this slider moves free and easy. You can test that by prying in between your pads and the rotor and watching if the caliper body moves back and forth. If it doesn’t, your slider may well be frozen also. I’ve never seen a bolt that mounts a caliper to a slider that had a “pinhead”. (Make sure that you are on the right bolt head.) When you talk about the “end of the slider bolt maybe being threaded on the end that is facing you but inside the caliper,” you are not picturing it correctly. Again, there are no threads on the slider (except internally, where the caliper bolt connects the caliper to the slider). Go online for an exploded view of your setup. Always wear safety glasses and never take sh*t from an inanimate object.

[BigpapaBo]

Yes-Kroil. Heat the bolt up, spray with Kroil, while its smoking, spray the bolt with dust spray(the kind you use to clean computer keyboards.- tilt the can upside down when spraying) this will suck the Kroil in. Let sit 15/30 min. Repeat.
I’ve not had a brake/suspension bolt withstand this.
Impact wrench (battery operated). Drink a shot of whiskey.

[Iscool]

Noted. Maybe I can turn up a decent 6 point metric wrench set for not too much money: Need 17 mm for this. Funds are tight, but, I hate to buy a single...

I hear ya there...

[Iscool]

I have on numerous occasions used a breaker bar or just the proper wrench and placed them in a position pointing down as much as possible...Lay down and get your foot on the wrench while holding on to some part under the car...Some would be amazed at how much more power one has in his legs compared to his arms...I have broken loose many caliper bolts in this fashion...

[Iscool]

I have on numerous occasions used a breaker bar or just the proper wrench and placed them in a position pointing down as much as possible...Lay down and get your foot on the wrench while holding on to some part under the car...Some would be amazed at how much more power one has in his legs compared to his arms...I have broken loose many caliper bolts in this fashion...

[TNoldman]

It’s not your poor maintenance but that of the previous owner(s). Time to replace the Calipers - don’t waste any more time. Do the job right. Good luck FR friend.

[minnesota_bound]

These guys finally loosened a bolt using heat.
https://www.youtube.com/watch?v=VWy_VelIn4w

[Paul R.]

Ok, yes, you are correct - I got confused by some of the info -- had it right originally -- the parts I am trying to loosen ARE the caliper BOLTS. Such as (on the right):

[HandyDandy]

Those bolts aren't known for giving the kind of trouble that you are running into. They'll be pretty tight but not knuckle busters. Also, the ones in the picture have a decent sized head (are yours different than those pictured?) It is more often that those sliders in your picture get frozen and can give you a real headache. You can use the prying back and forth between the pads and rotor to get an idea ahead of time whether or not one or the other of these sliders is frozen. Or, for example, while it is all still assembled, pry on the pad that is on the piston side to push the piston all the way in. Then get in between the back of the pad and the piston and pry that piston in until it is fully seated (something you'll need to do when replacing pads anyway). Now you should have plenty enough room to move the caliper body back and forth on the slides to find out what further trouble you might encounter. Obviously, if the piston won't retract, you need new calipers. If the pin, or pins are frozen you might work them free with heat applied to the caliper bracket.

[HandyDandy]

pin = slider

[WinMod70]

Those pins should drive out. The bolts, on right gold color, look to be what holds the caliber to the bracket. I’m thinking you should be able change the pads by just driving the pins out and leave the caliper mounted. Maybe not, as I said before I’m a GM guy.

[WinMod70]

Forgot something, if you really need those bolts out versus just the pins, I would bet the bolts were installed with lock tight, heat is definitely your friend when dealing removing bolts that have had lock tight applied, especially the red stuff.

[WinMod70]

Forgot something, if you really need those bolts out versus just the pins, I would bet the bolts were installed with lock tight, heat is definitely your friend when dealing removing bolts that have had lock tight applied, especially the red stuff.

[TNoldman]

The Slider Pins are secured by threads at the end where the Hex Head is located. The short Hex Head Bolts sevure the Caliper to the vehicle spindle. This is the starting point.

I have said before but I will say it again. Remove the Caliper to Spindle bolts. Disconnect the hydraulic brake line. Install new Caliper and Pads. Reconnect Hydraulic brake line and bleed brake lines.

If you can’t do that procedure get someone who can . Brakes are too important to not do correctly.
Good Luck.

I have Serviced Ford Vehicles for 60 years.

[Paul R.]

The Slider Pins are secured by threads at the end where the Hex Head is located. The short Hex Head Bolts secure the Caliper to the vehicle spindle. This is the starting point.

Right, that's what I recall from all the brake jobs I've done in the past (maybe 10, total, the last a few years ago -- sometimes if my vehicle is in a shop, already "up", and the timing is handy, I have the shop do the brake job.) And, I've observed mechanics doing 'em, but none recently. Some of the discussion and even You Tube vids got me thinking Fords were somehow different, and I was approaching the job incorrectly, but yes, removal of the Caliper to Spindle Bolt has always been the first step of any brake job I've done or observed.

So, I'm stuck at "Step 1" (hex head Caliper bolts frozen), and will have at it again, this evening. After that, it should go smoothly.

Needing to always replace the Caliper is what bothers me. What you are really saying is that Ford brake Calipers are crap & don't hold up any longer than the pads.* Geez...

I have not been at it quite as long (or intensely) -- only 40+ years (with about half the brake jobs on my vehicles done by shops, not me) and have never run into a caliper problem or replacement. Granted that this is our 1st Ford, and that we have a Toyota Matrix that may also need a caliper replaced. (It appears the local mechanic who did the last brake job on the Toyota did not apply any lubricant, anywhere.)

I finally heard back from my (not local) mechanic buddy. He has run a top notch shop about 400 miles north of here for about 40 years - it is a much higher corrosion problems area - and he tells me that out of their brake jobs, they replace calipers about 10% of the time. His "off the top of the head" inclination was that they may replace more Ford brake calipers than, say, Honda or Toyota, but they've never actually tracked that.

*This (Explorer) is "going to have to do" for a few years. After that, I think we'll hold out (and save more pennies) for a nice used Toyota Sequoia, next time...

Thanks for the info., and good luck in whatever is your next project, too!

[Paul R.]

The caliper bolts I’m dealing with have a shallower head than those in the pic, and that is definitely part of the problem. In the past, I’ve not had big problems with such (on other vehicles.)

My mechanic buddy who I finally was able to get in touch with last night says they use air impact wrenches on these because they do sometimes require more effort than can readily be applied with a conventional wrench. “Just grab the air impact wrench and be done with it.” Granted, he’s in a high corrosion problems area.

The brakes were working fine except for the pad wear. Everything that should push in-out seems to be moving around ok, the caliper pin bolts are just locked / won’t turn.