Red and blue loctite on caliper bolts?

[Ian Geary]

Afternoon all,

I was looking over the front brakes on our 2007 swift, and wanted to take the calipers off to inspect the piston and sliding action.

It's a simple setup - you hold the slider with a 15mm spanner and the end bolt is 13mm.

However, on both sides, the top end bolt has blue loctite on it, and the lower bolt has red loctite on it.

I had never seen this before, and Google throws no light on this practice.

Has anyone seen this before? Or is able to share some insight maybe?

I would say the top bolt was definitely aluminium (blue) whereas the lower bolt was rustier so looked steel (red). Same size though.


I've done them both up with blue loctite, as I was out of red.


Thanks

Ian

[Belle427]

I was under the impression it indicates the strength, blue for medium which can be easily taken apart with hand tools and red which required some heat.

[Jaybmw]

Someone been overally cautious. Absolutely no need for it

[Rowe]

Some pad kits come with fresh hardware.
It's probably more likely that someone has at some point fitted a new bolt and re-used one of the old one (as opposed to applying two different grades of loctite)

[E-bmw]

As others have said, it will likely be a case of all that was to hand, I wouldn't worry about it, it is not "a thing".

[MattyD803]

Over the years, I've replaced brake pads on a number of cars (mostly Japanese) and the genuine manufacturer 'full' front pad kits come with replacement bolts, pre-coated with BLUE thread lock compound.

I've never seen or heard of red being used for these bolts - I'd suggest re-coating with blue only, red is unnecessary for this application in my experience. What is more important, is torquing up correctly on refitting.

[Defcon5]

It’s an old gypsy trick.

[TwinKam]

Some of my stocks of new caliper slide bolts; some with red, some with blue, some with neither.



No rhyme, no reason. Don't worry.

[Ian Geary]

Ok thanks all.

Just wondered as it seemed a bit odd.

It's probably a mechanic removing just one bolt to swing the caliper up to do brake pads, and using whatever bolts they had to hand to replace it.

The torque is pretty low on these bolts , so I see why the thread lock is important.


Ian

[Chris32345]

Locktite is generally overkill for brakes but does add some peace of mind

[darreni]

I don't use either on cailper fixings, just torque to recommended spec.
As a note, blue loctite is medium strength & allows fixings to be removable with hand tools, red loctite is usually permanent & requires 300C plus heat to remove. I'd never use red on anything that may require removal at a later date.

[Ian Geary]

Yeah I normally wouldn't use it on brake calipers - and only if the manual called for it. Bit given it was on these ones I thought I would treat them to the low strength stuff.


I've used the super strength stuff occasionally and it's twisted the heads of bolts rather than undo them - that has been thrown away.