Anti-seize on brake caliper bracket?

[mrgrim007]

I just got done rebuilding the front-end on my 2002 Suburban (ball joints, pitman arm, etc.). The bolts that hold the brake caliper bracket to the knuckle always seem difficult to remove.

This time around, I decided to add anti-seize to each of the four bolts.

Now I’m second guessing myself and wondering if I should take them back out, clean off the anti-seize and possibly add some loctite instead?

Thanks

[ls1mike]

My entire adult life has been spent going to sea on, working around and maitaining Submarines.
We use anti-seize in some spots, but loctite in most areas were a locking device cannot be used or extra locking is required for Nylock fasteners.

GM installs your caliper bracket bolts with blue Loctite. You will probably be fine.

They are not worried so much about it backing out as they are about preventing shock, vibration and heat cycles from losening it up. It won't back out on it's own.
I doubt any of the shock, vibration or heat cycles will cause it do that either, but being connected to the steering knuckle/axle and being attached to an area that will heat up under heavy load they are just being safe. Vibartion will loosen even properly torqued fasteners over time.

I genearlly don't put any back on(I do on the truck and the Trans Am) but I don't anti-seize them either.

[Cummins12V98]

Grit dog wrote:
^You may have a good reason for that, but my experience in many brake jobs is that there is no harm in anti seize for the mounting bolts. Only benefit for the next person having to remove them.

Just did a brake job on my 01. The two bolts holding the caliper brackets had blue loctite. With all the force applied it’s a good idea!

[BenK]

am of the anti-seize and also know to back off the torque to offset via SAE30 spec for lubed vs dry

Also, need to understand the designer/engineer behind those torque requirements (recommendations)

Of course rotating engine component fasteners are lubed and should be tossed whenever they are loosened...the whole set. This includes head bolts

Then where the designer/engineer has that required/recommended torque is vs the fastener yield point. An example is the infamous Ford 6.0L ARP head bolts (part of the delete & fix so often mentioned)...they are torqued to 'yield'...meaning that they won't stretch anymore under the designed clamping force...but if there should be one or more instances exceeding that...it will go beyond that holding/clamping force and it will never have the same clamping force...even if you re-torque it

Most fastener applications has the designer/engineer decide how much

Some things are designed to be repaired, often and the designer/engineer should have taken that into their calculations.

Steel wheels has a coined area around the lug hole, while aluminum alloy wheels do NOT. Why alloy wheels need to be re-torqued after they have been loosened. I check 2 or 3 times. Then whether the lug nut is tapered or shouldered or washer'ed. makes a difference

Side note...if working on whatever down there on the suspension, replace fasteners with the same grade it came with. It has to do with how the designer/engineer expects things to break apart during a crash. Buddy's speed shop refused a customer who insisted on changing everything to grade 8...

[Grit_dog]

^You may have a good reason for that, but my experience in many brake jobs is that there is no harm in anti seize for the mounting bolts. Only benefit for the next person having to remove them.

[Cummins12V98]

mich800 wrote:
The OP noted caliper bracket not pins or caliper bolts. They do tend to be stubborn. I don’t think anti seize will hurt anything.

The Caliper mounting bracket bolts should NOT have anti seize on the threads they should have medium blue loctite. Be sure threads are clean and then apply loctite and torque to spec.

[STBRetired]

Grit dog wrote:

True statement, fasteners are cheap, but the labor to replace all the wheel studs on a vehicle every couple years? Holy carp! Be financially advantageous to never rotate your tires or just trade it in when your alarm clock says replace perfectly good wheel studs.
I will give you this, I've had a couple vehicles that the lug nutz basically wore out.
Haven't replaced a lug stud in idk how many years and those broke due to rust or a bad/loose wheel.

I replace them myself. The studs are fairly cheap. Just take the car to the race shop and do the work there. Can usually get one of the other guys to help. Don't think I would change them regularly if I had to pay the $160/hour shop rates.

Tires don't get rotated on the MH. When I put new tires on it (well, had commercial truck place do the work) I measured the length on all the studs and only found 1 that was longer than the rest. I had them replace just that one. Quick easy check with caliper while they were mounting tires on rims.

[Grit_dog]

STBRetired wrote:

Grit dog wrote:

Lol, really? By way of all your experience with engines, one would think you'd understand clamping force, slip critical connections, yield and non yield tensile strength, torque as it relates to tension etc.
You seriously replace the brake caliper bolts after using them twice and your wheel lugs after 4-5 tire rotations?
I don't believe you....

Yes, I actually do. It's not like I pull the calipers off every week. A set of pads usually lasts at least a couple of years. I've had several broken wheel studs which I attribute to the grease monkeys at the Ford dealer running the lug nuts down with their air impacts, even though I specifically ask that they hand torque them. I don't drive a lot of miles since retiring so I only need 1 or maybe 2 tire rotations per year. Working on the dragster has made me a bit of a nut when it comes to fasteners. Fasteners are cheap compared to what can happen if they fail. At least I don't safety wire everything on my car like we do on the dragster. Guess I'm just a bit extreme.

True statement, fasteners are cheap, but the labor to replace all the wheel studs on a vehicle every couple years? Holy carp! Be financially advantageous to never rotate your tires or just trade it in when your alarm clock says replace perfectly good wheel studs.
I will give you this, I've had a couple vehicles that the lug nutz basically wore out.
Haven't replaced a lug stud in idk how many years and those broke due to rust or a bad/loose wheel.

[mich800]

The OP noted caliper bracket not pins or caliper bolts. They do tend to be stubborn. I don’t think anti seize will hurt anything.

[Cummins12V98]

The slide bolts don't clamp anything they simply are a smooth surface for the caliper to move on. Basically they vibrated loose.

[Cummins12V98]

fj12ryder wrote:
Okay, that makes sense. Thanks.

Almost sounds like the bolts were undersized and stretching, then loosening up. The loctite wouldn't really address the issue, but it would keep the bolts from then falling out.

Pretty rare for caliper bolts to just fall out, but not unusual for the recommendation of loctite on those bolts. I agree that blue should be perfectly fine in most circumstances.

I am thinking PISS-POOR machining on the threads, ID and OD.

[STBRetired]

Grit dog wrote:

Lol, really? By way of all your experience with engines, one would think you'd understand clamping force, slip critical connections, yield and non yield tensile strength, torque as it relates to tension etc.
You seriously replace the brake caliper bolts after using them twice and your wheel lugs after 4-5 tire rotations?
I don't believe you....

Yes, I actually do. It's not like I pull the calipers off every week. A set of pads usually lasts at least a couple of years. I've had several broken wheel studs which I attribute to the grease monkeys at the Ford dealer running the lug nuts down with their air impacts, even though I specifically ask that they hand torque them. I don't drive a lot of miles since retiring so I only need 1 or maybe 2 tire rotations per year. Working on the dragster has made me a bit of a nut when it comes to fasteners. Fasteners are cheap compared to what can happen if they fail. At least I don't safety wire everything on my car like we do on the dragster. Guess I'm just a bit extreme.

[Grit_dog]

STBRetired wrote:
On my personal vehicle, I follow that same rule for any safety related items like brakes and suspension / steering. Anything else, like wheel studs, I will usually go 4 or five torquings before replacing.

Lol, really? By way of all your experience with engines, one would think you'd understand clamping force, slip critical connections, yield and non yield tensile strength, torque as it relates to tension etc.
You seriously replace the brake caliper bolts after using them twice and your wheel lugs after 4-5 tire rotations?
I don't believe you....

[STBRetired]

Rod bolts, head bolts, main bearing cap bolts are all put together using assembly lube so that you get the proper stretch when you torque them. Some anti-seize will not be a problem. Of greater concern is the number of times those bolts have been removed and re-torqued. Every time you torque that bolt you stretch it a bit further. Eventually, the bolt will fail, not by loosening, but by breaking because it was overstretched. On our race car, we replace any bolt that would be torqued more than twice. On my personal vehicle, I follow that same rule for any safety related items like brakes and suspension / steering. Anything else, like wheel studs, I will usually go 4 or five torquings before replacing.

[ACZL]

How about VW using a 14mm triple square bit to mount their calipers onto their vehicles? Course I don't have that part (NAPA does tho). WTH? Can't use regular bolts like everyone else?? UGH !!!!